S-12 Oil Pressure Drops - Komatsu WA250-6 Shop Manual

600 Troubleshooting of engine (S-mode)

S-12 Oil pressure drops

S-12 Oil pressure drops
General causes why oil pressure drops
Leakage, clogging, wear of lubrication system
q
Defective oil pressure control
q
Improper selection of oil (improper viscosity)
q
Deterioration of oil due to overheating
q
Confirm recent repair history
Degree of use of machine
Oil pressure monitor indicates low oil pressure
Non-specified oil is being used
Replacement of filters has not been carried out according to Operation and Maintenance
Manual
Oil pressure monitor
Oil level monitor indicates oil level drop
Oil level in oil pan is low
External hydraulic piping is leaking, crushed
Oil is milky or smells of diesel oil
Metal particles are found when oil pan is drained
Metal particles are found when oil filter is drained
Metal particles are found in oil filter
Inspect oil pan strainer, pipe directly
Oil pump rotation is heavy, there is play in oil pump
Valve and spring of regulator valve are fatigued, damaged
Inspect oil filter directly
If oil level sensor is replaced, oil level monitor indicates normally
WA250, 250PZ-6
Operated for long period
Indicates pressure drop at low idle
Indicates pressure drop at low, high idle
Indicates pressure drop on slopes
Sometimes indicates pressure drop
SEN03850-00
Causes
E
Q
w
Q w w w Q
w
w
w
w
w
w
q
q q
Remedy —
1
E E
Q w
Q
w
w Q
w
w
Q
q
q
q
q
19
40-600