Oil Pressure Drops - Komatsu ecot3 PC300LC-8 Shop Manual

40 Troubleshooting
S-12 Oil pressure drops
General causes why oil pressure drops
• Leakage, clogging, wear of lubrication system
• Defective oil pressure control
• Selection of oil by the temperature etc. specified in the Operation and
Maintenance Manual is not observed.
• Deterioration of oil due to overheating
Confirm recent repair history
Degree of use of
Operated for long period
machine
Oil pressure monitor indicates low oil pressure (if monitor is installed)
Non-specified oil is being used
Replacement of filters has not been carried out according to Operation and Maintenance Man-
ual
Indicates pressure drop at low idle
Oil pressure moni-
Indicates pressure drop at low, high idle
tor
Indicates pressure drop on slopes
(if installed)
Sometimes indicates pressure drop
Oil level monitor indicates oil level drop (if monitor is installed)
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 spring of regulator valve is fatigued, damaged
Inspect oil filter directly
If oil level sensor is replaced, oil level monitor indicates normally
PC300, 350-8
SEN02634-02
Cause
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Remedy
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