cooling system failure

8/20/2019 Cooling System Failure

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COOLINGSYSTEM

FAILURE



Cooling System

Probable Cause

Maintenance of

Cooling System.

Minimum points to be checked in thefield.

a) Heavy scale formation. (Refer Photo)

b) Overheat marks on piston skirtdiameter.

c) Overheat marks on intake and exhaustvalves.

d) Overheat marks on cylinder head/s,near cup plug area, head may crack atvalve bridges.

e) Liner packing rings hard or mutilatedand cut. (Refer Photo)

f) Burnt / mutilated water grommets.

g) Hardened “O” rings of water manifold.

h) Water cooled turbo failures.



Cooling System

Probable Cause

Effects of bad

maintenance of

Cooling System.

Minimum points to be checked in thefield.

a) Beginning of piston scuffing / scoringprocess. (Refer Photo)

b) Four point scuffing / scoring of piston/s.

c) 100 % scuffing / scoring of pistons.d) Cracking of piston after scuffing from oil

ring groove area. (Refer Photo)

e) Breakage of piston from cracked area.

f) Liner “o” ring mutilated and breakage.

g) Heavy pitting on liner, water pump &liner cavity in the block, puncture of oilcooler or after cooler tubes & injectorsleeves also in extreme cases. (ReferPhoto)



Cooling System

Probable Cause

Effects of bad

maintenance of

Cooling System.

Minimum points to be checked

in the field.a) Con rod bearing seizure due to

blocking of lube oil cooler waterpassage with foreign particles. (ReferPhoto)

b) Water pump seal failures due to dirtcirculation through cooling system.

c) 100 % scuffing / scoring of pistons.

d) Pin hole or cracked liner/s.

e) Cylinder head injector sleeve failures.



Cooling System

How toidentify….

Scale formation,

dirt in coolingsystem without

opening much

components.

Minimum points to be checked

in the field.a) A thick layer of scale in radiator top

tank.

b) Heavy scoring on thermostat cup seal

seat area.c) Heavy scoring on water pump housing

below impeller area.



KV 16 liner OD shows heavy pitting



KV 12 liner shows heavy pitting



NT 495 injector sleeve pitted



Oil cooler tube puncture due to water.



NT 855 water pump impeller pitted badly.



NT 855 water pump housing shows circular

deep grooves, debries in coolant.



6BT water pump impeller badly pitted

compared with new water pump.



NT 855 lube oil cooler water passage

blocked with foreign particles.



KV 16 after cooler air passage blocked due

to water leakage.



Piston shows four point scuffing on skirt

diameter.



Piston shows 100% scuffing on skirt

diameter.



RB side piston cracked & LB side piston

broken after cracking.



Liner crevice seal mutilated due to

overheating.



A thick layer of scale formation on oil cooler

element.



A thick layer of scale deposits on liner outer

dia.



Water cooled turbo coolant port reduced

due to scale.



A thick layer of scale deposits in Cylinder

Head coolant cavity.



A thick layer of scale formation on liner OD.



A thick layer of mud accumulation in

Cylinder Block at oil cooler cavity.



Liner OD shows a thick layer of scale + lube

oil deposits.

cooling system failure

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