Oil Pressure Drops - Komatsu 114E-3 Series Shop Manual

40 Troubleshooting
S-12 Oil pressure drops
General causes why oil pressure drops
Leakage, clogging, wear of lubrication system
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Defective oil pressure control
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Improper selection of oil (improper viscosity)
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Deterioration of oil due to overheating
q
Confirm recent repair history
Degree of use of machine Operated for long period
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 Mainte-
nance Manual
Oil pressure monitor
(if installed)
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 and spring of regulator valve are fatigued, damaged
Inspect oil filter directly
If oil level sensor is replaced, oil level monitor indicates normally
114E-3 Series
Indicates pressure drop at low idle
Indicates pressure drop at low, high idle
Indicates pressure drop on slopes
Sometimes indicates pressure drop
SEN00458-01
Causes
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Remedy
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