Engine Does Not Start - Komatsu Galeo PC138US-8 Shop Manual

40 Troubleshooting
S-2 Engine does not start
a) Engine does not turn
General causes why engine does not turn
Seized parts inside engine
q
o See "S-4 Engine stops during operations"
Defective electrical system
q
Confirm recent repair history
Degree of use of machine
Condition of horn when
starting switch is turned ON
Battery electrolyte is low
Battery terminal is loose
When starting switch is turned ON, there is no operating sound from battery relay
When starting switch is turned to START, starting pinion does not move out
When starting switch is
turned to START, starting
pinion moves out, but
Inspect flywheel ring gear directly
When specific gravity of electrolyte and voltage of battery are measured, they are low
Turn starting switch OFF,
connect cord, and carry out
troubleshooting at ON
PC138US, USLC-8
Operated for long period
Horn does not sound
Horn volume is low
Speed of rotation is low
Makes grating noise
Soon disengages again
Makes rattling noise and does not turn
There is not voltage (20 – 30 V) between battery relay terminal B
and terminal E
When terminal B and terminal C of starting switch are connected,
engine starts
When terminal B and terminal C at safety relay outlet are
connected, engine starts
Even if terminal B and terminal C at safety relay outlet are
connected, engine does not start
When terminal at safety switch and terminal B at starting motor are
connected, engine starts
SEN02469-01
Causes
E E
Q Q
w
w
w
Q w
Q Q
w
w
Q
q
q
q
q
Remedy
1
w
w
w
w
Q Q
q
q
q
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