33 0 14MB
CARBON DEPOSITS –– 25 15 9 –– 1
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE land. Carbon deposits onFOR the ring lands indicate lack of gas PROCEDURE INSPECTION sealing at the respective rings. If the deposits are thick, the IF PART OFbeA smooth RING IS ATOF PISTONS &MISSING LINERS surface may and shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT – 21 – – 39 –
TEMPT TO FIND THE MISSING PART(S). MISSder wall. Thisprovide contact may locally away IF theTHE oil film, rePiston rings a gas tight sealwipe between the piston and ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings.
PARTS I, II & III SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the 2010 ring down and out Version 1.0 – November – 43 –
If cleaning boxes orcreate air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards thescavenge cylinder this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR
MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
LEAKING OIL – LO scavenge port inspection, broken rings are identi-
oil Iffied is Sluggish by:found on the piston, determine if it is fuel oil or lube oil. Fuel oil be blackring and (C). sticky, indicating a fuel is leaking. Lube oil will Sticking Collapsed CLEAN, SMOOTH – valve * will be brown and non-sticky, indicating it could be from exhaust Running surfaces the piston lineranare worn Lack of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secvalve. bright, rings move freely in the grooves, are well oiled, and intact.
y p o nC
o i t a str
tion).
OPTIMAL –
*
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
n o em
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is
D
Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. Keep cooling water and cooling INTACT RING oil – circulating during in-
*
Running surfaces of the rings are worn bright, smooth, clean, withspection so possible leakages can be detected. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS –2–
SCOPE OF SCAVENGE PORT INSPECTIONS:
–– 25 15 9 –– 3
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE land. Carbon deposits on the ring lands indicate lack of gas
The following shall be carried out during a scavenge port inspection: Visual examination in accordance with requirements of MAN Inspection Through Scavenge Ports form. Measurement of the remaining depth of the pressure relief grooves (CL grooves), ring groove clearance and piston burn-away in accordance with MAN Condition Monitoring Report (Port Inspection) form. Inspection of the cylinder liner running surface through the scavenge ports. Photos taken of piston crown, top land, piston rings, piston skirt, piston rod, cylinder liner and scavenge receiver. Photos are required for any surfaces that are wiped down or cleaned, see taking photos section for details in Part II. Inspection of non-return flaps. Inspection of water mist catcher.
– 21 – MAN B&W Two-Stroke Enginesare thick, the sealing at the respective rings. If the deposits – 39 – IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT TEMPT TO FIND THE MISSING PART(S). IF THE MISSder wall. Thisprovide contact maytight locally away the the piston oil film,and rePiston rings a gas sealwipe between ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 – SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE.
PRACTICES FOR SCAVENGE PORT INSPECTIONS
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), 1.0 Surface section). Version persed around the circumference of the piston. BLOW-BY:
Ring movement is described as: PART Loosea During
LEAKING OIL – LO scavenge port inspection, broken rings are identi-
oil Iffied is found on the piston, determine is fuel oil&orTurbo lube oil. Fuel Sluggish Supplement to the MANif itDiesel by: oil be black and sticky, indicating a fuel valve is leaking. Lube oil will Sticking form titled Collapsed ring (C). CLEAN, SMOOTH – * will be brown and non-sticky, indicating it could be from an exhaust Running surfaces theThrough piston and liner are worn Scavenge Port LackInspection of “elasticoftension” (SLrings and ST, cylinder Ring Movement secvalve. bright, rings move freely in the grooves, are well oiled, and intact.
tion).
1. Always use MAN Diesel & Turbo sheets Inspection through Scavenge Ports and Cylinder Condition Report when submitting scavenge port inspection results. Blank inspection forms are available in APPENDIX. 2. Conduct scavenge inspections on a monthly or as soon thereafter basis. 3. Always pre-view the last scavenging port inspection prior to accomplishing a new port inspection. 4. Photos and comments in this booklet are an overview of the MAN Diesel & Turbo Instruction Manual Vol. 1, Operation Manual, Chapter 707. Refer to Chapter 707 for complete descriptions of procedures for scavenge port inspections, cylinder conditions, piston conditions, ring conditions, factors influencing cylinder wear, and cylinder lubrication. 5. The scavenge port inspection should be carried out at the first stop after a long voyage, e.g. by anchoring if possible, to obtain the most reliable result with regard to the effectiveness and sufficiency of the cylinder lubrication and the combustion cycle (complete or incomplete). A misleading result may be obtained if the scavenge port inspection is carried out after arrival at harbour, since manoeuvring and low speed running requires increased oil dosage. *one star at a photo indicate a perfect condition. **two stars at a photo indicate machining marks still invisible.
I
OPTIMAL –
*
Fractured ring(s) (BO, BN or SP). November 2010
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. Keep cooling water and cooling INTACT RING oil – circulating during in-
*
Running surfaces of the rings are worn bright, smooth, clean, withspection so possible leakages can be detected. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS –4–
–– 25 15 9 –– 5
HOW TO USE THE MAN Diesel & Turbo FORM Inspection through Scavenge Port The form on the next page is the MAN Diesel & Turbo form titled Inspection through Scavenge Port, a blank form is provided in the APPENDIX. The left column on the MAN Diesel & Turbo form lists GENERAL CATEGORIES, the next column lists SPECIFIC CONDITIONS within each GENERAL CATEGORY. The scavenge port inspection involves the identification of SPECIFIC CONDITIONS within each of the GENERAL CATEGORIES.
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE land. Carbon deposits on the ring lands indicate lack of gas – 21 – sealing at the respective rings. If the deposits are thick, the – 39 –
General Specific IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT Category Conditions
TEMPT TO FIND THE MISSING PART(S). MISSder wall. Thisprovide contact may locally away IF theTHE oil film, rePiston rings a gas tight sealwipe between the piston and Location ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 –
SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT FOR ASTERISK is used on the ment isFOUND, essential.INSPECT THEAnTURBOCHARGER form when a specific condition MISSING PART(S) AND/OR DAMAGE. is favorable, i.e., Intact, No de-
Ring movement is described as:posit, Loose, Clean, Smooth, Partial view of MAN form, full page view on opposite page Location
General Category
Specific Conditions When conducting a scavenge port inspection on a unit, start by asking what is the status of each GENERAL CATEGORY in relationship to the SPECIFIC CONDITION. Once that determination has been made, write the symbol for that condition in the box that corresponds to the location, i.e. topland, ring land number or ring number.
Loosea During
No sludge LEAKING OIL –Optimal LO scavenge port inspection, brokenorrings are identi-
oil Iffied is Sluggish by:found
on the piston, determine if it is fuel oil or lube oil. Fuel oil be black and (C). sticky, indicating a fuel is leaking. Lube oil will Sticking Collapsed ring CLEAN, SMOOTH – valve * will be brown and non-sticky, indicating it could be from exhaust Running surfaces the piston lineranare worn Lack of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secvalve. bright, rings move freely in the grooves, are well oiled, and intact.
tion).
OPTIMAL –
*
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. Keep cooling water and cooling INTACT RING oil – circulating during in-
*
Running surfaces of the rings are worn bright, smooth, clean, withspection so possible leakages can be detected. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS –6–
–– 25 15 9 –– 7
Often some deposits will accumulate on the side of the top
PART I
RING BREAKAGE/COLLAPSE land. Carbon deposits on the ring lands indicate lack of gas
PART I of this booklet was developed to provide a photographic representation of each piston and liner condition listed on the MAN Diesel & Turbo Inspection through Scavenge Port form.
– 21 – sealing at the respective rings. If the deposits are thick, the – 39 – IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT TEMPT TO FIND THE MISSING PART(S). IF THE MISSder wall. Thisprovide contact maytight locally away the the piston oil film,and rePiston rings a gas sealwipe between ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 – SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE. Ring movement is REPRESENTATIONS described as: PHOTOGRAPHIC OF SPECIFIC CON Loose LEAKING OIL – LO DITIONS LISTED ON MAN DIESEL & TuRBO INDuring a scavenge port inspection, broken ringsFORM are identi oil If is the piston,SCAVENGE determine if it PORT is fuel oil or lube oil. Fuel Sluggish SPECTION THROUGH fied by:found on oil be blackring and (C). sticky, indicating a fuel is leaking. Lube oil will Sticking Collapsed CLEAN, SMOOTH – valve * will be brown and non-sticky, indicating it could be from exhaust Running surfaces the piston lineranare worn Lack of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secvalve. bright, rings move freely in OPTIMAL the grooves, are well oiled, and intact. – * tion). All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY: Fractured ring(s) (BO, BN or SP). Blow-by, Missingthe ringleakage (M). of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – * indicated by black, dry areas on the rings and by larger black DEPOSIT * wall which can only dry zones on the upperNOpart of the– liner Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact. following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS.
GENERAL CATEGORIES on the MAN form match the name on the tab at the bottom of each booklet page (black arrow). SPECIFIC CONDITIONS on the form are represented by photographs (red arrow) in this booklet.
EXCESSIVE DEPOSIT - EC
EXCESSIVE DEPOSIT - EC (Close Up of Top Photo)
CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
POLISHED DEPOSIT - PC
PISTON DEPOSITS
necessary to continuously refresh the liner surface to counteract bore polish. Keep cooling water and cooling INTACT RING oil – circulating during in-
*
Running surfaces of the rings are worn bright, smooth, clean, withspection so possible leakages can be detected. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS –8–
–– 25 15 9 ––
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE land. Carbon deposits on the ring lands indicate lack of gas – 21 – sealing at the respective rings. If the deposits are thick, the – 39 – IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT TEMPT TO FIND THE MISSING PART(S). IF THE MISSder wall. Thisprovide contact maytight locally away the the piston oil film,and rePiston rings a gas sealwipe between ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 – SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE.
Ring movement is described as:
INTACT PISTON CROWN – * An intact piston crown has a minor layer of carbon, no burn-away (elephant skin).
Loosea During
LEAKING OIL – LO scavenge port inspection, broken rings are identi-
oil Iffied is Sluggish by:found on the piston, determine if it is fuel oil or lube oil. Fuel oil be blackring and (C). sticky, indicating a fuel is leaking. Lube oil will Sticking Collapsed CLEAN, SMOOTH – valve * will be brown and non-sticky, indicating it could be from exhaust Running surfaces the piston lineranare worn Lack of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secvalve. bright, rings move freely in the grooves, are well oiled, and intact.
tion).
OPTIMAL –
*
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
BU
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT
PISTON CROWN BURNING – BU Further information concerning piston crown burning can be found in PART III.
Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. Keep cooling water and cooling INTACT RING oil – circulating during in-
*
PISTON CROWN
Running surfaces of the rings are worn bright, smooth, clean, withspection so possible leakages can be detected. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS – 25 15 11 –
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE CARBON DEPOSITS land. Carbon deposits on the ring lands indicate lack of gas – 21 – Often will rings. accumulate on the side the top sealingsome at thedeposits respective If the deposits are of thick, the – 39 –
IF PART OFbe A smooth RING on IS MISSING “M”), ATland. Carbon deposits the ring lands indicateon lack gas surface may and shiny from(Condition rubbing theofcylinRING MOVEMENT TEMPT FIND THE MISSING PART(S). THE MISSsealing atTO theprovide respective rings. Ifseal the deposits are thick, the der wall. This contact may locally wipe away IF the oil film, rePiston rings a gas tight between the piston and ING BROKEN RING PART(S) CANNOT BE LOCATED, INsurface be smooth andincreased shiny from rubbing onand theabove cylincylinder liner wall. The seal occurs bywear gas sulting inmay micro-seizure and ofpressure liner rings. – 43 –
SPECT THE EXHAUST GAS RECEIVER, THE SCAVENGE der Thisthe contact locally wipe the oiland film,out reand wall. behind pistonmay ring forcing the away ring down If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THE AIRofBOX, IF STILL sulting inthe micro-seizure and increased wear linerring and rings. towards cylinder ToSCAVENGE create this seal, free movebefore and after cleaning. NOT INSPECT THE TURBOCHARGER FOR ment isFOUND, essential.
MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
scavenge port inspection, broken rings are identi Sluggish fied by: Sticking Collapsed ring (C). CLEAN, SMOOTH – * Running Lack
surfaces the piston liner are worn of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secbright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
tion).
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
* Running of piston willpiston be–worn addition, the NOrings DEPOSIT * orbright. be seensurfaces when overhauling the whenIn exchanging DEPOSIT dry zones on the upperNOpart of the– liner wall which can only
rings will surfaces move freely inthis their grooves, be well oiled around Running of In piston rings will be worn bright. Inevenly addition, the the exhaust valve. booklet, blow-by is indicated by the the of the piston, and intact. ringscircumference will move freely in their grooves, be well oiled evenly around following conditions: BLACK OVERALL, BLACK PARTIALLY the circumference of the piston, and intact.
and BLACK RING ENDS.
CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For Too much cylinder lubricating oil can create calcium deposits on large bore engines it can be necessary to use a wooden block and the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. INTACT RING –
*
Running surfaces of the rings are worn bright, smooth, clean, without scratches, move freely in the grooves and are well oiled.
RUNNING SURFACE, BLACK OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
CARBON DEPOSITS – 12 –
– 25 13 15 –
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE land. Carbon deposits on the ring lands indicate lack of gas – 21 – sealing at the respective rings. If the deposits are thick, the – 39 – IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT TEMPT TO FIND THE MISSING PART(S). IF THE MISSder wall. Thisprovide contact maytight locally away the the piston oil film,and rePiston rings a gas sealwipe between ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 – SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE.
Ring movement is described as: Loosea During
LIGHT DEPOSIT – LC
scavenge port inspection, broken rings are identi Sluggish fied by: Sticking Collapsed ring (C). EXCESSIVE CLEAN, SMOOTH DEPOSIT––*EC Running Excessive surfaces carbon oftension” the piston are(SL the rings result and over lubrication liner are or worn im Lack of “elasticdeposits and ST,ofcylinder Ring Movement sec-
*
proper bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact. tion).combustion. All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT
MEDIUM DEPOSIT- MC
Ring movement is checked by pressing on each ring with a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For POLISHEDoil DEPOSIT – PCcalcium deposits on Too much cylinder lubricating can create large bore engines it can be necessary to use a wooden block and Ifthe the deposits abnormally thick, the carbon deposits may the be pistons, seeare photo below. Calcium deposits rubbing against a hammer. smooth liner canand leadshiny to mechanical from rubbing “bore against polish” theand cylinder destroy wall. theThis oil film, can leading scuffing (SC, Surface section). Over lubricaresult in to locally wiping away the oilCondition film, causing micro-seizures and tion also suppresses corrosion completely. Controlled corrosion is increased wear of liner and rings.
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. INTACT clover RING –leafing (Surface Condition In some instances, mechanical
*
Running CL) surfaces of thevisible rings are worn bright, smooth, clean,higher withsection, can occur, as vertical grooves of slightly out scratches, move freely in the grooves and are well oiled. wear in between the lubricating quills.
RUNNING SURFACE, BLACK OVERALL – B
PISTON DEPOSITS
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 25 15 –
RING BREAKAGE/COLLAPSE – 21 – – 39 –
IF PART OF A RING IS MISSING (Condition “M”), ATRING MOVEMENT TEMPT TO provide FIND THE MISSING MISSPiston rings a gas tight sealPART(S). between IF theTHE piston and ING BROKEN RING PART(S) CANNOT BEpressure LOCATED, INcylinder liner wall. The seal occurs by gas above – 43 –
SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
scavenge port inspection, broken rings are identi Sluggish fied by: Sticking Collapsed ring (C). CLEAN, SMOOTH – * Running Lack
surfaces the piston liner are worn of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secbright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
tion).
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For Too much cylinder lubricating oil can create calcium deposits on large bore engines it can be necessary to use a wooden block and the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. INTACT RING –
*
Running surfaces of the rings are worn bright, smooth, clean, without scratches, move freely in the grooves and are well oiled.
RUNNING SURFACE, BLACK OVERALL – B
RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 16 –
– 25 15 17 –
RING BREAKAGE/COLLAPSE – 21 – – 39 –
IF PART OF A RING IS MISSING (Condition “M”), ATRING MOVEMENT TEMPT TO provide FIND THE MISSING MISSPiston rings a gas tight sealPART(S). between IF theTHE piston and ING BROKEN RING PART(S) CANNOT BEpressure LOCATED, INcylinder liner wall. The seal occurs by gas above – 43 –
SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
COLLAPSED RING – C Collapse occurs if the gas pressure behind the ring is built up too slowly. With inadequate outward pressure behind the ring, combustion gas can penetrate between the liner and the ring, violently forcing the ring inwards, into the ring groove. The sudden shock loading will eventually lead to fracture, particularly if the ring ends slam against each other.
scavenge port inspection, broken rings are identi Sluggish BROKEN OPPOSITE RING GAP – BO fied by: Sticking Ring breakage opposite the ringSMOOTH gap is evidence of localized over Collapsed ring (C). CLEAN, –*
stressing of the ring material during installation Running surfaces the piston and liner in arepermaworn Lack of “elasticoftension” (SLrings and ST, cylinder Ringresulting Movement secnent deformation, causing blow-by and broken rings bright, rings move freely in the grooves, are well oiled, and intact.
tion).
OPTIMAL –
*
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
The slow pressure build-up behind the rings can be due to:
Carbon deposits in the ring groove (MC and EC, Deposits section). Insufficient vertical ring clearance (PART III, Ring Groove Measurement). Partial sticking (ST, Ring Movement section) Poor sealing between the ring and the ring groove floor. Clover-leafing (CL, Surface Condition section). Ring end chamfers. Too large ring-edge radii. Continual striking against wear ridges (WR, Surface Condition section), or other irregularities in the cylinder wall.
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS. BROKEN NEAR GAP – BN CHECKING RING MOVEMENT If seen on topring female partbreakage caused turning Ring movement is checked by pressing onoften each ring withby a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For edges in the liner top
Too much cylinder lubricating oil can create calcium deposits on large bore engines it can be necessary to use a wooden block and the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. INTACT RING –
*
Running surfaces of the rings are worn bright, smooth, clean, without scratches, move freely in the grooves and are well oiled.
RUNNING SURFACE, BLACK OVERALL – B SEVERAL PIECES – SP
RING BREAKAGE
RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 18 –
– 25 19 15 –
RING BREAKAGE/COLLAPSE – 21 – – 39 –
IF PART OF A RING IS MISSING (Condition “M”), ATRING MOVEMENT TEMPT TO provide FIND THE MISSING MISSPiston rings a gas tight sealPART(S). between IF theTHE piston and ING BROKEN RING PART(S) CANNOT BEpressure LOCATED, INcylinder liner wall. The seal occurs by gas above – 43 –
SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
scavenge port inspection, broken rings are identi Sluggish fied by: Sticking Collapsed ring (C). CLEAN, SMOOTH – * Running Lack
surfaces the piston liner are worn of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secbright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
tion).
All piston rings have oil at (B theoredges and the Condition oil film is evenly dis Blackish appearance (B), Surface section). persed around the circumference of the piston. BLOW-BY:
Fractured ring(s) (BO, BN or SP).
Blow-by, Missingthe ringleakage (M).
of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
ENTIRELY MISSING – M
indicated by black, dry areas on the rings and by larger black
If part of a ring is missing, attempt to find the missing part(s). If the missing broken ring part(s) cannot be located, inspect the exhaust gas receiver and the bottom of the scavenge air box, if still not found, inspect the turbocharger for missing part(s) and/or damage.
dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For Too much cylinder lubricating oil can create calcium deposits on large bore engines it can be necessary to use a wooden block and the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. INTACT RING –
*
Running surfaces of the rings are worn bright, smooth, clean, without scratches, move freely in the grooves and are well oiled.
RUNNING SURFACE, BLACK OVERALL – B
RING BREAKAGE
RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 25 21 –
RING MOVEMENT – 21 – Piston rings provide a gas tight – 39 –seal between the piston and
cylinder liner wall. The seal occurs by gas pressure above RING MOVEMENT and behind the piston ringtight forcing the ring down and and out Piston rings provide a gas seal between the piston towards the wall. To occurs create this seal,pressure free ring above movecylinder linercylinder wall. The seal by gas – 43 –
mentbehind is essential. and the piston ring forcing the ring down and out If cleaning boxes air receiver, take photos both towards thescavenge cylinder wall. Toorcreate this seal, free ring movebefore after is cleaning. Ring movement described as: ment isand essential.
Loose
Ring movement Sluggish
Loose Sticking
Sluggish
Sticking
is described as:
CLEAN, SMOOTH – *
Running surfaces of the piston rings and cylinder liner are worn bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by RING pressing on each ring with a wooden CHECKING MOVEMENT stick through a scavenge port. Turn the up and For Ring movement is checked by pressing onpiston each ring with down. a wooden TOO necessary MUCH OIL –toOuse a wooden block and large through bore engines it can be stick a scavenge port. Turn the piston up and down. For Too much cylinder lubricating oil can create calcium deposits on alarge hammer. bore engines it can be necessary to use a wooden block and
the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 22 –
– 25 23 –
Sticking Ring
– 21 – – 39 –
RING MOVEMENT RING SHOULD MOVE & SPRING BACK FREELY IN RING GROOVE WHEN PUSHED
PISTON RING MOVEMENT
Piston rings provide a gas tight seal between the piston and cylinder liner wall. The seal occurs by gas pressure above – 43 –
and behind the piston ring forcing the ring down and out If cleaning boxes air receiver, take photos both towards thescavenge cylinder wall. Toorcreate this seal, free ring movebefore after cleaning. ment isand essential.
Ring movement is described as:
LOOSE – *
Loose
Sluggish
Sticking
CLEAN, SMOOTH – *
Running surfaces of the piston rings and cylinder liner are worn bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
WHEN HANDLE IS PULLED AWAY THERE IS A MOMENTARY DELAY BEFORE THE RING SPRINGS BACK OUT
PISTON RING MOVEMENT
WHEN HANDLE IS PISTON PULLED RING Blow-by, theAWAY leakage of combustion gas past the piston RING Scavenge DOES NOT SPRINGBox, NO SLUDGE – * rings, isBACK the result collapse or breakage. It is MOVEMENT OUTof ring sticking, Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY STICKING – ST and BLACK RING ENDS.
SLUGGISH – SL
CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden TOO MUCH OIL – O stick through a scavenge port. Turn the piston up and down. For Too much cylinder lubricating oil can create calcium deposits on large bore engines it can be necessary to use a wooden block and the pistons, see photo below. Calcium deposits rubbing against the a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
CALCIUM DEPOSITS
RING MOVEMENT
(Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 25 –
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
CLEAN, SMOOTH – * Running surfaces of the piston rings and cylinder liner are worn bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS.
TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 26 –
– 25 27 –
VERTICAL SCRATCHES – 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
RUNNING SURFACE, BLACK PARTLY – (B)
CLEAN, SMOOTH – * Running surfaces of the piston(VERTICAL) rings and cylinder liner are worn SCRATCHES –S bright, ringsismove freely the grooves, well oiled, Scratching caused byinhard abrasive particles fromand theintact. fuel oil, OPTIMAL – are
*
from a broken turbocharger on the All piston rings ring haveoroilfrom at the edges andintake. the oil Scratches film is evenly dispiston ring running surface is one of the first signs of abrasive persed around the circumference of the piston. BLOW-BY: particles, and can be observed during scavenge port inspections.
Blow-by, the leakagedoofnot combustion gas past i.e., the the piston usually, micro-seizures scratching, ring Scavenge Box,occur NO from SLUDGE –* rings, isremains the result of Hardness ring sticking, or breakage. is surface soft. can collapse be checked with a file, Itsee
Scavenge Box, NO SLUDGE – * RECOGNIZING MICRO this section MAN Diesel indicated by black, drySEIZURES areas on inthe rings and and by larger black & Turbo Plate 70704. dry zones on the upper part of the liner wall which can only
be seen when overhauling the piston or when exchanging Because the top edge is the initial point the exhaust valve. In this booklet, blow-by is indicated by of the Scratching damage is found contact, particle wear primarily affects the upper ring face, horizontal ring surface and ring groove.
on the top of the ring where following conditions: BLACK OVERALL, BLACK PARTIALLY
the hard particles enter beand BLACK RING ENDS. tween the ring and the liner.
BLACK RING ENDS >100MM – BR
TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the Cross Section
of Ring liner can lead toFace mechanical “bore polish” and destroy the oil film, of Ring leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
SCRATCHES (VERTICAL) – S Piston Skirt
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 28 –
– 29 25 –
MICRO-SEIZURES:
RECOGNIZING MICRO-SEIZURES
Micro-seizures are the result of break down of the lube oil
Micro-seizures on a running will have a vertically– 39surface –
film, causing metal to metal contact. The contact will cause
striped appearance, and be relatively “hard”, which refers to
a high friction and high temperature that will change the
the result of a FILE TEST.
appearance of the ring surface. The cylinder oil film break – 43 –
down is in most cases caused by borepolish. May be due
To conduct a file test, use a new, finely cut file to file across
to overlubrication causing built up of deposits polishing the
If cleaning scavenge boxes receiver, takeno photos both the hardened surface. If theorfileairleaves almost scratch, it
liner running surface.
before andthe after cleaning. indicates surface is covered by a hard glaze, the result
LOCAL micro-seizures are limited to part of a ring circum-
70704 for additional information concerning the FILE TEST.
ference. However, because rings turn in their grooves, LO-
The file test can of course only take place on a dismantled
CAL micro-seizures on a ring can produce micro-seizures
piston ring.
of micro-seizure hardening. See MAN Diesel & Turbo Plate
all the way around the cylinder liner as the ring rotates in
CLEAN, SMOOTH – *
the ring groove, creating a condition known as ALL OVER micro-seizures.
Running LOCAL &surfaces ALL OVER of the MICRO-SEIZURES piston rings and cylinder liner are worn bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
To identify LOCAL micro-seizures before they develop into
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
*
it is important to check the exhaust and cam (manoeuvring)
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is
sides as well as the forward and aft piston ring conditions
indicated by black, dry areas on the rings and by larger black
using a mirror.
dry zones on the upper part of the liner wall which can only
ALL OVER micro-seizures, when conducting an inspection
Scavenge Box, NO SLUDGE – *
be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS. LOCAL MICRO-SEIZURES – mz TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B ALL OVER MICRO-SEIZURES – MZ Notice in the top photo the micro-seizures are limited to the center scavenge port. In the bottom photo micro-seizures can be seen in all 3 scavenge ports. This is the distinction between LOCAL and ALL OVER micro-seizures.
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 30 –
– 25 31 –
FACTORS INFLUENCING CYLINDER WEAR
ACTIVE & INACTIVE MICRO-SEIZURES
It is vital that the system be free – 39 – of condensation and water. Condensation produces sulphuric acid corrosion, water breaks down cylinder lubrication. – 43 –
To minimize condensation observe the following best pracIf cleaning scavenge boxes or air receiver, take photos both tices: before and after cleaning. Optimize the temperature of the liner wall by maintaining
In extreme seizures, burrs can form on edges of rings.
cooling water outlet temperatures within the specified limits.
Keep cooling water temperature differences across the cylinder units between 12°-18°C at MCR.
CLEAN,the SMOOTH – * best practices: To minimize water observe following Running the piston andmist cylinder liner functions are worn Checksurfaces that theofdrain for therings water catcher
*
bright, rings move freely in OPTIMAL the grooves, are well oiled, and intact. properly to prevent water droplets– from entering the cylinders. Flat Ring Face
All piston rings at the edges and thefitting oil filmaccording is evenly dis Check waterhave mistoilcatcher for correct to persed around the circumference of the piston. BLOW-BY:
Service Letter
Burrs (Top Inset Photo)
Blow-by, Check
for thefree leakage standing of combustion water in the mist gas catcher. past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
Whenever a cylinder a indicated byinspecting black, dry areas on theliner, ringsuse andabymirror largerand black Cross Section of Ring
bright light a upper flash photo the condition of dry zones onor the part ofto theinspect liner wall which can only
Face of Ring
Irregular Marks (Vertical Scratches)
Hardened
injectors, exhaust valve and be seen when overhauling thecylinder piston orhead. when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY
STILL ACTIVE MICRO-SEIZURES – MAZ
SCUFFING: and BLACK RING ENDS. Scuffing is the result of oil film breakdown. With the cylinder walls no longer able to retain an oil film, frictional interaction between the cylinder and TOO wall MUCH OILring – O surfaces occurs. Due
to the heat, ring and cylinder friction weld, harden, Too much cylinder lubricating oilsurfaces can create calcium deposits on the pistons, seedevelop photo below. Calcium deposits rubbing against the and seizures on both surfaces. liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
Face of Ring
Smooth & soft along edges
Still hard in center area of ring face
OLD MICRO-SEIZURES – OZ
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 32 –
– 33 25 –
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
WEAR RIDGES NEAR SCAVENGER PORTS – WR Ring breakage can occur by rings repeatedly CLEAN, SMOOTH – * moving across a wear ridge. Running surfaces of the piston rings and cylinder liner are worn
*
bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact. All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
MACHINING MARKS STILL VISIBLE – ** A cylinder liner in good condition will have “wave-cut” machining marks visible on the complete running surface. The wave-cut surface is a single spiraled 0.01-0.02mm deep groove. The groove acts as a pocket for the cylinder lubricating oil to maintain a proper oil film so as the piston rings move across the groove, oil is deposited on the rings. If the wave cut pattern is worn away or the cylinder wall microstructure changes the cylinder liner will not properly distribute cylinder oil and scuffing can occur.
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS.
TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the liner can lead to mechanical “bore polish” and destroy the oil film, RINGS SCUFFING – SC leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B Extreme scuffing can cause burrs on edges
LINER SCUFFED – SC
CALCIUM DEPOSITS
RINGS SCUFFING (CLOSE-UP) (Provided as a reference only, not –a SC listed condition) Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 34 –
– 35 25 –
The clover-leaf formation in a liner is described by heavy
– 39 –
CLOVER LEAFING: wear patterns in the cylinder liner between the lubricating quills (between red lines), with less wear outside of the heavy wear areas (between red & yellow lines). – 43 –
In extreme cases the liner bore may resemble a clover leaf,
If cleaning scavenge boxes or air receiver, take photos both
thus the name. Clover-leafing can be the result of micro-sei-
before and after cleaning.
zures, misalignment, polished deposits, improper lubrication or water disrupting the oil film on the cylinder wall.
CLEAN, SMOOTH – RINGS * SHARP EDGED Running surfaces of the piston rings andTOP cylinder liner are worn & BOTTOM – T/B bright, rings move freely in OPTIMAL the grooves, well edges oiled, and intact. will be sharp – areRing
*
roundings All piston rings have oil at the edges and when the oiloriginal film is evenly dishave been worn away, persed around the circumference of the piston. BLOW-BY: Rings with sharp edges.
but without burrs.
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY Cross section view looking down at a clover leafed cylinder liner Lubricating Quills
Cylinder Liner
WITH SOFT EDGES: and RINGS BLACK RING ENDS. Ring roundings from start. 26-35 . . . . . . 0,8 mm 42-50 . . . . . . 1,2 mm TOO MUCH OIL – O 60-70 . . . . . . 1,6 mm Too much cylinder lubricating oil can create calcium deposits on 80-98 . . . . . . 2,0 mm the pistons, see photo below. Calcium deposits rubbing against the
Piston Crown
liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
Clover leaf wear is identified by heavy wear patterns between lubricating quills
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
CLOVER LEAF WEAR – CL
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 36 –
– 25 37 –
When the piston is positioned at approximately TDS, inspect the piston rod through the scavenge ports.
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
PISTON RODCLEAN, (Close-Up), SMOOTH CORROSION –* – CO Running surfaces of the piston rings and cylinder liner are worn bright, rings move freely in OPTIMAL the grooves, – are well oiled, and intact.
*
PISTON ROD, SMOOTH – *
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston. BLOW-BY:
Blow-by, the leakage of combustion gas past the piston Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black dry zones on the upper part of the liner wall which can only be seen when overhauling the piston or when exchanging the exhaust valve. In this booklet, blow-by is indicated by the following conditions: BLACK OVERALL, BLACK PARTIALLY and BLACK RING ENDS.
TOO MUCH OIL – O
PISTON ROD, CORROSION – CO
Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
RUNNING SURFACE, BLACK OVERALL – B
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil
SURFACE CONDITION
sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 39 –
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
OPTIMAL – * All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the OPTIMAL – piston.
*
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston.
Scavenge Box, NO SLUDGE –
*
Scavenge Box, NO SLUDGE – *
TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on TOO MUCH OIL – O the pistons, see photo below. Calcium deposits rubbing against the Too much cylinder lubricating oil can create calcium deposits on liner can lead to mechanical “bore polish” and destroy the oil film, the pistons, see photo below. Calcium deposits rubbing against the leading to scuffing (SC, Surface Condition section). Over lubricaliner can lead to mechanical “bore polish” and destroy the oil film, tion alsotosuppresses corrosion completely. corrosion is leading scuffing (SC, Surface Condition Controlled section). Over lubricanecessary to continuously refresh the liner Controlled surface tocorrosion counteract tion also suppresses corrosion completely. is Scavenge Box, SLUDGE – S bore polish.to continuously necessary refresh the liner surface to counteract bore polish.
CALCIUM DEPOSITS CALCIUM DEPOSITS
(Provided as a reference only, not a listed condition) (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 40 –
– 41 –
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
SLIGHTLY DRY – D
BLACK OIL – BO
Running surface of piston rings dry but oil is still visible on ring lands.
Surfaces covered with black oil indicates poor combustion combined with excessive cylinder oil. Surfaces covered with black oil OPTIMAL – canpiston also be the have resultoil of at manoeuvring. All rings the edges and the oil film is evenly dis-
*
persed around the circumference of the piston.
Scavenge Box, NO SLUDGE –
*
Scavenge Box, NO SLUDGE – *
TOO MUCH OIL – O
VERY DRY – DO
Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the
Too little cylinder lubricating oil can result in break down of the oil film between the piston rings and the cylinder liner leading to adhesive contact and possible scuffing of rings and liner.
liner can lead to mechanical “bore polish” and destroy the oil film, leading to scuffing (SC, Surface Condition section). Over lubrication also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
LUBRICATION CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
Scavenge Box, NO SLUDGE – * Scavenge Box, NO SLUDGE – *
Scavenge Box, NO SLUDGE –
*
Scavenge Box, NO SLUDGE – *
Scavenge Box, SLUDGE – S
Scavenge Box, SLUDGE – S
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil Scavenge Box, MUCH SLUDGE – MS sludge and sludge carbon can deposits in the scavenge boxes. Too much contaminate systemair oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SCAVENGE SCAVENGE COMPARTMENTS COMPARTMENTS
– 44 –
– 45 –
– 39 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
Scavenge Receiver, NO SLUDGE – *
FLAPS (NON-RETURN VALVES), INTACT – *
Alert:water washing from defect water mist catcher could cause a very clean scavenge air receiver.
Check the non-return valves (flap valves) for easy movement and damage. OPTIMAL –
*
All piston rings have oil at the edges and the oil film is evenly dispersed around the circumference of the piston.
Scavenge Box, NO SLUDGE –
*
Scavenge Box, NO SLUDGE – *
TOO MUCH OIL – O Too much cylinder lubricating oil can create calcium deposits on the pistons, see photo below. Calcium deposits rubbing against the
Scavenge Receiver, SLUDGE – S * Normal picture. Indicate good cylindercondition.
liner can lead to mechanical “bore polish” and destroy the oil film, FLAPS BENT leading to scuffing (SC, Surface Condition section). Over lubrica(Provided as a reference only, not a listed condition) tion also suppresses corrosion completely. Controlled corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish.
CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
Scavenge Receiver, MUCH SLUDGE – MS Remove any oil sludge and carbon deposits in scavenge receiver.
Scavenge Box, MUCH SLUDGE – MS FLAPS, Move Freely Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
LUBRICATION CONDITION
SCAVENGE COMPARTMENTS
SCAVENGE COMPARTMENTS COMPARTMENTS SCAVENGE
– 46 –
– 47 –
– 43 –
If cleaning scavenge boxes or air receiver, take photos both before and after cleaning.
INTACT – * Inspect the condition of the locking wire for the piston skirt bolts. A loose locking wire can indicate one of the screws is loose or the wire is broken.
WATER MIST CATCHER, OUTLET SIDE Check for gaps and missing bolts that cause gaps between the mist catcher and the casing. In the top photo the arrows indicate where to check for loose or missing bolts, the circle indicates where to check for gaps. In the lower photo a gap exists.
WATER MIST CATCHER
Scavenge Box, NO SLUDGE –
*
Scavenge Box, NO SLUDGE – *
Scavenge Box, SLUDGE – S
Depending on the temperature and humidity of the ambient air and the temperature of the cooling water, water may condensate on the coldest air cooler tubes of the air cooler. Water mist catchers are installed directly after the air coolers to prevent water droplets from entering the cylinders. If water enters the cylinders, the oil film on the cylinder liner can be ruptured, resulting in scuffing and cloverleafing on the liner surfaces. Inspect the water mist catcher for cracks in the frame and correct mounting during scavenge port inspections. A broken or loose mounting may cause an upstream gap at the bottom of the water mist catcher elements. Air on the upstream side will short-circuit the element and cause water running down through the element to be sprayed downstream out through the water mist catcher. The water spray from the broken water mist catcher may enter the cylinder units.
It is very important that the water mist catcher drains function properly and that the water mist catcher is fit-
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
ted correct in the frame. if any doubt remove the casing covers to check.
SCAVENGE COMPARTMENTS
SCAVENGE SCAVENGE COMPARTMENTS COMPARTMENTS
57 49 ––– 65 53 61 51 ––– 59
SCAVENGE REQUIRED METHOD A,PHOTOS: PORT MEASURING INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Top land consider rodPiston tical clearance specified on width the (CL Groove), the and
Scavenge Data Plate. shape of the receiver vernier Cylinder Piston rings The ring stem groove iswide an indicator of gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. groove. If thethe ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For an accurate a vernierit could be due to a malfunction coolerofsystem causPART IIthe gauge with a stem that will sit of on theair bottom the groove ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge SCAVENGE PORT INSPECTION TOOLS & air.
TAKING PHOTOS PART III Version 1.0
Supplement to the MAN 2010 Diesel & Turbo form November titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatWhen taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool. functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 61 51 ––– 59
REQUIRED SCAVENGE METHOD A,PHOTOS: PORT MEASURING INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Top land consider rodPiston tical clearance specified on width the (CL Groove), the and
Scavenge Data Plate. shape of the receiver vernier Cylinder Piston rings The ring stem groove iswide an indicator of gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. groove. If thethe ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For an accurate a vernierit could be due to a malfunction coolerofsystem causgauge with a stem that will sit of onthe theair bottom the groove ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge air.
PART III
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatWhen taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool. functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 61 51 ––– 59
– 52 –
REQUIRED SCAVENGE METHOD A,PHOTOS: PORT MEASURING INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Top land consider rodPiston tical clearance specified on width the (CL Groove), the and
Scavenge Data Plate. shape of the receiver vernier Cylinder Piston rings The ring stem groove iswide an indicator of gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. groove. If thethe ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For an accurate a vernierit could be due to a malfunction coolerofsystem causgauge with a stem that will sit of onthe theair bottom the groove ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge air.
PART III
Forward and aft scavenge port running surfaces.
Cylinder wall above and below scavenge ports.
Cylinder covers
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, Coat-
Injectors
When taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool.
Exhaust valve
functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF.
Cylinder wall wear ridges
A mirror, with tiltable telescopic handle is used to inspect:
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos.
INSPECTION TOOLS
Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 55 61 51 ––– 59
– 54 –
SCAVENGE REQUIRED METHOD A,PHOTOS: PORT INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Photos aMEASURING good method forcrowns, detecting and the documenting Prior to are inspecting the maximum Piston crown Prior to measuring inspecting Piston ring groove skirt Scavenge review box the verconditions such asthe machine marks (**), wear ridges (WR), permissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Scavenge Top land rodPiston receiver tical clearance specified on width the Data Plate. clover leafing consider (CL), scuffing (SC), micro-seizures (MZ) and (CL Groove), the and shape of the vernier Cylinder Piston rings The ring stem groove iswide an indicator of polishing. gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. If oil orduring water isFor found on topwear of ameasurement, piston, use photos docugroove. If thethe ring groove rate suddenly increases it actual depth. an accurate use atovernier ment the condition of the valve, cylinder head and could be due to a malfunction air cooler causgauge with a stem that willexhaust sit of onthe the bottom ofsystem the groove injectors. ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge air.
Photo taken with camera’s flash switched ON. Since this photo includes a broken ring, carbon deposits and sharp edges on rings, details in the photo are important, but concealed by the glare from the camera’s flash.
PART III
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatWhen taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool. functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate.
Photo taken in figure above
Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
TAKING PHOTOS
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 61 57 51 ––– 59
SCAVENGE REQUIRED METHOD A,PHOTOS: PORT MEASURING INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Top land consider rodPiston tical clearance specified on width the (CL Groove), the and
Scavenge Data Plate. shape of the receiver vernier Cylinder Piston rings The ring stem groove iswide an indicator of gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. groove. If thethe ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For an accurate a vernierit could be due to a malfunction coolerofsystem causgauge with a stem that will sit of onthe theair bottom the groove ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge air.
PART III
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatWhen taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool. functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 Version 1.0 OFF.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of November 2010
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
PART III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 59 61 51 ––– 59
– 58 –
PART III
SCAVENGE REQUIRED METHOD PROPER SELECTION A,PHOTOS: PORT MEASURING INSPECTION Take OFpiston VERNIER RING photos TOOLS GROOVE of GAUGE thereview CLEARANCE following: Prior to inspecting the crowns, the maximum
Condition Monitoring Report (Port inspection) Vessel:
In accordance with
IMO no:
No. of cylinders: Hours since last overhaul:
Eng. builder:
Eng. type:
Mk.:
Eng. no.:
Eng. hrs.:
Checked by: Date (yymmdd):
Piston Scavenge Piston crown Before Prior to measuring inspecting the the ring depth groove skirt of the a clearance, Pressure Relief review box Groove the verpermissible burn-away values on Piston Data Plate.
Voyage info Weeks per port calls: Cyl. oil consumption (l/24 hrs):
Normal service load (% of MCR): at load %:
Lub. part load control: Cyl. oil type:
Lub. type: Sulph. %:
CL grooves
MAN Diesel & Turbo
Nominal CL depth, new ring, mm:
Minimum CL depth, mm:
Piston Top land consider rodPiston (CL tical Groove), clearance specified the on width the and
No. of CL grooves:
d
Round
Round
form, Condition Monitoring Report (Port inspection), PART III of
Round
Cylinder No. (Where accessible)
Round
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Depth, d (mm)
CL groove no. 1 CL groove no. 2
down inspection. groove. actual during depth. If thethe For ring an groove accurate wearmeasurement, rate suddenlyuse increases a vernierit
CL groove no. 3 CL groove no. 4 CL groove no. 5 CL groove no. 6
this booklet provides
Remaining round (Y/N)
a
Piston ring no. 2
pictorial
descrip-
tion of measurement procedures
pertain-
ing to Pressure Relief
Scavenge Data shape Plate. of the receiver vernier Cylinder Piston rings The gauge’s ring stem groove endclearance (Fig. 1). If measurement iswide an indicator of theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the measurement wear place on chromium plating inare the ring willphotos indicate groove isthat less than the
gauge could be with due a stem to a malfunction onthe theair bottom coolerofsystem the groove causthat will sit of ing water 3 & 5). to enter the cylinder, a malfunction of the cylinder (Figs. lube system or abrasive particles from fuel oil or scavenge
Piston Rings Ring hours Coating thickness (1/1000 mm) Piston ring no. 1 Piston ring no. 3 Piston ring no. 4
Ring grooves & Piston crown Crown hours E = (180°)
Piston crown burning
Ring groove clearance, H Measured at Exhaust side (Exh.) and/or Manoeuvre side (Man.)
Measuring positions to be indicated in degrees (0° - 360°)
H
F = (90°)
A = (270°)
M = (0°)
2 mm
Ring groove clearance, H (mm) Groove no. 1, Exh.
air.
PART III
Groove no. 1, Man. Groove no. 2, Exh. Groove no. 2, Man. Groove no. 3, Exh. Groove no. 3, Man.
Groove (CL groove) depth,
ring
groove
clearance and piston
Groove no. 4, Exh. Groove no. 4, Man. Piston crown High topland (Y/N):
Oros piston (Y/N):
Bronze ring (Y/N):
Max burning 1 (mm) Position 1 (degrees) Max burning 2 (mm) Position 2 (degrees) Max burning 3 (mm) Position 3 (degrees) Remarks:
Rel. 2009-02-13
crown burn-away. MEASURING PRESSURE RELIEF GROOVE (CL GROOVE) DEPTH
STEP 2: Insert a thin feeler gauge between the top of the ring and ring groove to determine if the ring is resting against the top of the ring groove. If there is a clearance, follow STEPS 3 - 6 on top and bottom. The clearance is the total of both the top and floor (bottom) clearance measurements.
Fig. 4
Measure the Pressure Relief Groove (CL Groove) depth
Chromium Plating
Prior to inspecting the piston crowns, review the maximum permissible burn-away values on the Piston Data Plate in the MAN DIESEL MAINTENANCE MANUAL.
Fig. 6
The pressure relief groove depth shall not be less than 1mm, notify CSC immediately if the depth is less than 1mm. Enter all measurements on the MAN Diesel PISTON CONDITION MONITORING (Port Inspection) form.
PRESSURE RELIEF GROOVE (CL GROOVE) DEPTH MEASUREMENT
Fig. 1
page.
Insert the piston template through a scavenge port and place evenly across piston crown.
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove
Fig. 5
STEP 5: How many times the groove is measured with the feeler gauge will vary depending on the condition of the ring groove and the person doing the inspection.
functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF. and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags).
STEP 3: Insert a thin feeler gauge between the ring and the floor until a slight resistance is felt. The feeler gauge may go deep into the ring groove. Do not try to force the
STEP 4: Insert a slightly thicker feeler gauge between the ring and the floor until a slight resistance is felt. The feeler gauge will not go into the ring groove as far.
When taking the measurement, verify that the stem of the vernier gauge is sitting on the bottom of the Pressure Relief Groove (CL Groove).
When taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
Chromium Plating On Floor Wears Faster
feeler gauge into the groove. Use only light pressure.
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, Coat-
Check for burn-away and cracks (elephant skin) around the entire circumference of the piston crown. If elephant skin is found, look at the area from several positions to get a sense of the depth of the cracks in the elephant skin area.
2mm
STEP 6: As the feeler gauge thickness increases, the depth to which the gauge can be inserted into the groove will decrease. Consider the measurement complete when the feeler gauge can only be inserted 2 – 4mm into the groove. At this point, the feeler gauge thickness is the ring groove clearance. Enter the ring groove clearance depth on the PISTON CONDITION MONITORING (Port Inspection) form.
RING GROOVE CLEARANCE
Enter piston crown burn-away values and locations on the MAN Diesel PISTON CONDITION MONITORING (Port Inspection) form. Record the length and depth of cracks.
PISTON CROWN BURNING
Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away Fig. 2of– pistons WRONG values and and rings, locations on the for talking close up photos see Taking The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The vernier gauge stem end is narrow The work light provides soft light for theChromium photo,Plating without the ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Vernier Gauge TAKING Stem
PART III
PHOTOSPressure Relief Groove
2 mm Fig. 3 – CORRECT
(CL Groove)
Fig. PART 3 – CORRECT III
PRESSURE (CLPISTON GROOVE) Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION MONITORING (Port Inspection) form. DEPTH MEASUREMENT RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 65 53 61 51 ––– 59
– 60 –
MEASURING PRESSURE RELIEF GROOVE (CL GROOVE) DEPTH
SCAVENGE REQUIRED METHOD A,PHOTOS: PORT MEASURING INSPECTION Take RING photos TOOLS GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Piston Top land consider rodPiston tical clearance specified on width the (CL Groove), the and
Scavenge Data Plate. shape of the receiver vernier Cylinder Piston rings The ring stem groove iswide an indicator of gauge’s endclearance (Fig. 1). If measurement theliner stem is tooDamage (Fig. 2) the Before andtaking after arethe required fordepth items wiped the wear place on chromium plating inare the ring measurement willphotos indicate groove isthat less than the
down inspection. groove. If thethe ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For an accurate a vernierit could be due to a malfunction coolerofsystem causgauge with a stem that will sit of onthe theair bottom the groove ing water to enter the cylinder, a malfunction of the cylinder (Figs. 3 & 5). lube system or abrasive particles from fuel oil or scavenge air.
Fig. 4 Measure the depth of the pressure relief groove. The depth is an indicator of piston ring wear.
PART III
Supplement to the MAN Diesel & Turbo form titledPiston Crown Template, VerFrom left, MAN Diesel & Turbo PISTON CONDITION MONITORING (Port nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatWhen taking close-up use the camera’s MACRO entire circumference of photos, the piston crown. If elephant skin is ing Layer Measuring Tool. functionlook andatturn the camera’s flash Use the work light found, it from several angles and estimate the depth Version 1.0 OFF.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page.
Fig. 1
Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove (CL groove). ances must not exceed the value specified on the Piston Data Plate. Top of Ring The vernier gauge stem end is too wide to sit on the bottom of the groove 2mm Fig. 5 When taking the measurement, verify that the stem of the vernier gauge is sitting on the bottom of the Pressure Relief Groove (CL Groove). Vernier Gauge Stem
Pressure Relief Groove
Groove) A bright light is not only used for general (CL lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft light theChromium photo,Plating without the vernier gauge stem end isfor narrow ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the flash glare concealing details. groove. To measure the ring groove clearance at the point of maximum wear, the feeler gauge is only inserted 2mm into the ring groove when measuring.
INSPECTION TOOLSChromium Plating On Floor Wears Faster
Fig. 6 The pressure relief groove depth shall not be less than stated on the Piston Data Plate. Enter all measurements on the MAN Diesel & Turbo PISTON CONDITION MONITORING (Port Inspection) form.
PRESSURE RELIEF GROOVE (CL GROOVE) DEPTH MEASUREMENT
Vernier Gauge TAKING Stem
2 mm
PHOTOSPressure Relief Groove (CL Groove)
Fig. PART 3 – CORRECT III
Enter the ring groove RELIEF clearanceGROOVE depth on the CONDITION PRESSURE (CLPISTON GROOVE) MONITORING (Port Inspection) form. DEPTH MEASUREMENT
RING GROOVE CLEARANCE PISTON CROWN BURNING
57 ––– 63 65 53 61 51 ––– 59
– 62 –
METHOD B, MEASURING RING GROOVE CLEARANCE
STEPINSPECTION 2:Take Insert a TOOLS thin SCAVENGE REQUIRED METHOD A,PHOTOS: PORT MEASURING RING photos GROOVE of thereview CLEARANCE following: PROPER SELECTION OFpiston VERNIER GAUGE Prior to inspecting the crowns, the maximum
feeler gauge between the top of the ring and ring Scavenge Top land groove Piston rod tical clearance specified on width the Plate. (CL Groove), consider the and Data shape of the receiver vernier to determine ifPiston the
Chromium Plating Piston Scavenge Piston crown Prior to measuring inspecting the ring groove skirt review box the verpermissible burn-away values on Piston Data Plate. Before the depth of the a clearance, Pressure Relief Groove Cylinder Piston rings Damage The ring stem groove iswide an indicator of gauge’s end (Fig. 1).against If measurement theliner stem (Fig. 2) the ring isclearance resting the is too Before andtaking after photos arethe required items wiped the wear place on chromium plating inare the ring topwill of the ring groove. If for measurement indicate groove depth isthat less than the
there isan a accurate clearance, foldown the inspection. groove. If the ring groove wearmeasurement, rate suddenlyuse increases actual during depth. For a vernierit – 6 onoftop could be due to STEPS a malfunction coolerofsystem causgauge with alow stem that3will sit onthe theair bottom the groove and bottom. The clearChromiumofPlating On ing water to enter the cylinder, a malfunction the cylinder (Figs. 3 & 5). ance is the total of both Floor Wears Faster lube system or abrasive particles from fuel oil or scavenge
air.
STEP 1: Run the turning gear so the piston is in the downstroke. If the rings have good movement, the rings will move to the top of the ring groove. If the ring rests on the top of the groove, taking ring groove measurements are simplified by checking the top of the ring as seen in Step 2. Then, if the ring is actually resting against the top, feeler gauge measurements can be performed on the floor of the ring groove as illustrated in Steps 3 – 6. If not, feeler gauge measurements must be made at the top and the floor. The clearance will be the total of the two measurements.
the top and floor (bottom) clearance measurements.
PART III
STEP 3: Insert a thin feeler gauge between the Supplement to the MAN Diesel & Turbo form ring and the floor until a titled From left, MAN Diesel & Turbo Crown Template, Verslight resistance is Piston felt. PISTON CONDITION MONITORING (Port The feeler gauge may go nier Gauge, Soft Metal Drift, Camera, Feeler Gauge, Pencil, deep into the ring groove. Inspection) Check burn-away and cracks (elephant skin)Mallet, around the Marker,for Mirror, Flashlight, Large Screw Driver, CoatDoclose-up not tryTool. to force the feelWhen taking photos, use the camera’s MACRO entire circumference of the piston crown. If elephant skin is ing Layer Measuring er the groove. functionlook andat turn the into camera’s flash Use the work light found, itgauge from several angles and estimate the depth Version 1.0 OFF. Use only light pressure.
November 2010 as cracks. the camera’s source. This willsurfaces eliminateand reflection Also include cleanlight rags for wiping down two 20 of
and glare flash, see top for photo on the next liter (5 gl.) from pails the (1 tocamera’s carry tools, the other rags). page. 1 STEP 4: Insert Fig. a slightly Using a feeler gauge, measure top and bottom clearances between When selecting a vernier gauge, verify thicker feeler gauge be-that the stem end is not too the ring and the ring groove. The total of the top and bottom clearwide for the Pressure Relief Groove tween the ring and (CL the groove). ances must not exceed the value specified on the Piston Data Plate. floor until a slight resistance isTop felt.of Ring The feeler The vernier gauge stem end is too wide willbottom not goofinto to gauge sit on the the the groove ring groove as far. 2mm
STEP 5: How many times the groove is measured Vernier with theGauge feeler gauge will vary Stem depending on Pressure Relief Groove (CL Groove) A bright lightthe is condition not only used of the for ringgeneral lighting, but also
Enter piston crown burn-away values and and rings, locations on the for talking close up photos see Taking Fig. 2of– pistons WRONG
groove and the person doing the inspection. Ring grooves wearthe faster in two 1) camera’s light source. OFF and using work lightareas. as the Top of Ring The chromium plating on the floor of the The workThe light provides soft theChromium photo,Plating without the vernier gauge end isfor narrow STEP 6: Asstem thelight feeler ring groove. 2) The edge of the ringgroove enough to sitouter on the bottom of the gauge thickness increasflash glare concealing details. groove. To measure the ring groove cleares, the depth to which the ance at the point of maximum wear, the gauge can be inserted into feeler gauge is only inserted 2mm into the groove will decrease. the ring groove when measuring. Consider the measureINSPECTION TOOLSChromium Plating On Floor Wears Faster ment complete when the
The photo above was MONITORING taken with the camera’s flash switched PISTON CONDITION (Port Inspection) form. Photos.
Verniercan only be feeler gauge Gauge TAKING PHOTOSPressure Relief Groove inserted 2 – 4mm into the Stem (CL Groove) groove. At this point, the feeler gauge Fig.thickness 3 – CORRECT PART IIIis the ring groove clearance.
2 mm
Enter ring clearance depth CONDITION Enter the the ring groove groove RELIEF clearanceGROOVE depth on on the the PISTON CONDITION PRESSURE (CLPISTON GROOVE) MONITORING MONITORING (Port (Port Inspection) Inspection) form. form.
DEPTH MEASUREMENT
RING GROOVE CLEARANCE
RING GROOVE CLEARANCE PISTON CROWN BURNING
CARBON DEPOSITS –– 65 25 15 9 ––
Often some deposits will accumulate on the side of the top
RING BREAKAGE/COLLAPSE Prior inspecting the on piston crowns, thelack maximum land. to Carbon deposits the ring landsreview indicate of gas – 21 – permissible burn-away values Data sealing at the respective rings. If the Piston deposits arePlate. thick, the – 39on – IF PART OFbeA smooth RING IS ATsurface may andMISSING shiny from(Condition rubbing on“M”), the cylinRING MOVEMENT
TEMPT TO FIND THE MISSING PART(S). MISSder wall. Thisprovide contact may locally away IF theTHE oil film, rePiston rings a gas tight sealwipe between the piston and ING BROKEN RING PART(S) CANNOT BE LOCATED, INcylinder wall. The sealincreased occurs bywear gas sulting inliner micro-seizure and ofpressure liner andabove rings. – 43 –
SPECT THE the EXHAUST GASforcing RECEIVER, THE SCAVENGE and behind piston ring the ring down and out If cleaning scavenge boxes or air receiver, take photos both AIR RECEIVER ANDwall. THEToSCAVENGE AIR BOX, IF STILL towards the cylinder create this seal, free ring movebefore and after cleaning. NOT ment isFOUND, essential.INSPECT THE TURBOCHARGER FOR MISSING PART(S) AND/OR DAMAGE. Ring movement is described as: Loosea During
LEAKING OIL – LO scavenge port inspection, broken rings are identi-
oil Iffied is Sluggish by:found on the piston, determine if it is fuel oil or lube oil. Fuel oil be blackring and (C). sticky, indicating a fuel is leaking. Lube oil will Sticking Collapsed CLEAN, SMOOTH – valve * will be brown and non-sticky, indicating it could be from exhaust Running surfaces the piston lineranare worn Lack of “elasticoftension” (SLrings andand ST, cylinder Ring Movement secvalve. bright, rings move freely in the grooves, are well oiled, and intact.
tion).
OPTIMAL –
*
All piston have oil and at (B thecracks and the Condition oilskin) film isaround evenly dis Blackish Check forrings burn-away appearance oredges (B), Surface (elephant section). the persed around the circumference of the piston. BLOW-BY: Fractured ring(s) (BO, BN piston or SP).crown. If elephant skin is entire circumference of the
Blow-by, Missing the ring of combustion gas past the found, look at leakage it(M). from several angles and estimate the piston depth Scavenge Box, NO SLUDGE – * rings, is the result of ring sticking, collapse or breakage. It is of cracks.
Scavenge Box, NO SLUDGE – *
indicated by black, dry areas on the rings and by larger black
*
DEPOSIT dry zones on the upperNOpart of the– liner wall which can only Running of piston ringsthe willpiston be wornorbright. addition, the be seensurfaces when overhauling whenIn exchanging rings will move freely in their grooves, be well oiled evenly the exhaust valve. In this booklet, blow-by is indicated around by the the circumference of the piston, and intact.
following conditions: BLACK OVERALL, BLACK PARTIALLY
and BLACK RING ENDS. CHECKING RING MOVEMENT Ring movement is checked by pressing on each ring with a wooden LEAKING WATER TOO MUCH OIL –– OLW stick through a scavenge port. Turn the piston upIf and down. For Water on a piston indicates a cooling system water is found, Too much cylinder lubricating oil can create leak. calcium deposits on large bore engines it can be necessary to use a wooden block and it is pistons, important tophoto determine what the cause is. rubbing against the the see below. Calcium deposits a hammer. liner can lead to mechanical “bore polish” and destroy the oil film, Viewed a mirror or photo,Condition does it appear theOver leak lubricais from leading by to either scuffing (SC, Surface section). the head, exhaust valve,completely. injectors orControlled another source? tion cylinder also suppresses corrosion corrosion is
Scavenge Box, SLUDGE – S
necessary to continuously refresh the liner surface to counteract bore polish. Enter Keep piston coolingcrown waterburn-away and cooling values oil and locations during on the inINTACT RING – circulating
*
Running surfaces of theMONITORING rings are worn bright, smooth, clean, withPISTON spection CONDITION so possible leakages can (Port be detected. Inspection) form. out scratches, move freely in the grooves and are well oiled.
PISTON BLACK CROWN RUNNING SURFACE, OVERALL – B
PISTON DEPOSITS RING BREAKAGE CALCIUM DEPOSITS (Provided as a reference only, not a listed condition)
RING MOVEMENT
Scavenge Box, MUCH SLUDGE – MS Too much sludge can contaminate system oil. Remove any oil sludge and carbon deposits in the scavenge air boxes.
SURFACE CONDITION
LUBRICATION CONDITION SCAVENGE COMPARTMENTS PISTON CROWN BURNING
– 70 –
Technical Service Phone +45 33 85 11 00 Fax +45 33 85 10 49 [email protected] Emergency phone – after office hours: +45 20 48 94 40
Ordering of this booklet (80€): [email protected]
MAN PrimeServ – a service brand of MAN Diesel & Turbo
Copyright © MAN Diesel & Turbo · Subject to modification in the interest of technical progress. · 1510-0162-00ppr Nov 2010 Printed in Denmark
MAN Diesel & Turbo PrimeServ Copenhagen Teglholmsgade 41 2450 Copenhagen SV, Denmark www.mandieselturbo.com