S-11 Oil Becomes Contaminated Quickly - Komatsu PC88MR-10 Shop Manual

40 Troubleshooting
Troubleshooting of engine (S-mode)

S-11 Oil becomes contaminated quickly

Oil becomes contaminated quickly.
Failure
Related
If any failure code is displayed, perform troubleshooting for that code first.
information
No. Cause
Improper fuel used
1
Improper oil used
2
Black exhaust gas at KDOC
3
muffler outlet.
Excessive blowby gas
4
Defective seal on
5
turbocharger turbine side
Excessive refilling of oil
6
Dirty oil cooler element
7
Broken or worn piston ring
8
Worn or damaged valve
9
guide or stem seal
40-530
(D37-B20-400-A-Z0-A)
Point to check, remarks
Fuel other than specified one is used.
Oil other than specified one is used.
Check exhaust gas color at KDOC muffler
outlet (see standard value table).
(Reference: See Testing and adjusting,
"Testing exhaust gas color".)
Measured blowby pressure exceeds
standard value.
Blowby pressure is still high after KCCV
filter element is replaced.
Rotate turbocharger shaft and check for
play.
(Move turbocharger vanes with hand in axial
and radial directions to make judgment.)
Check oil level for excessive refilling.
(If oil level is excessive, oil will reach high
temperatures and early deteriorates.)
Visually check oil cooler element for
contamination.
(Contaminated oil cooler element can
increased oil temperature.)
Measured blowby pressure exceeds
standard value.
Blowby pressure is still high after KCCV
filter element is replaced.
Measure compression pressure (see
Standard value table).
(Reference: See Testing and adjusting,
"Testing compression pressure".)
Check valve guide and stem seal.
Remove cylinder head, and check inside
diameter of guide and stem seal for
damage.
(Reference: See "Maintenance standards".)
Remedy
Use proper fuel
specified in Operation
and Maintenance
Manual.
Use proper oil
specified in Operation
and Maintenance
Manual.
Perform
troubleshooting for "S-
9 Exhaust smoke is
black".
Perform following
checks.
Replace turbocharger.
Refill with oil to correct
oil level.
Clean or replace oil
cooler element.
Replace piston ring or
correct its installation.
Replace valve guide
and stem seal.
PC88MR-10