Engine Does Not Start - Komatsu PC200-8M0 Shop Manual

600 Troubleshooting of engine (S-mode)
S-2 Engine does not start
S-2 Engine does not start
a) Engine does not crank
General causes why engine does not crank
q
Internal parts of engine seized.
oSee "S-4 Engine stops during operations"
q
Defective electrical system
q
Defect in hydraulic pump
Check recent repair history.
Machine operation
hours
Condition of horn
when starting switch
is turned ON
Battery electrolyte level is low.
Battery cable terminal is loose
When starting switch is turned ON, no operating sound is heard from battery relay.
When starting switch is turned to START, starter pinion does not plunge.
When starting switch
is turned to START,
starter pinion
plunges, but:
Check flywheel ring gear.
Specific gravity of electrolyte and voltage of battery are low.
Turn starting switch to
OFF position and
connect cable, and
perform troubleshoot-
ing with starting
switch at ON.
PC200, 200LC, 220, 220LC-8M0
Operated for long period
Horn does not sound.
Horn volume is low.
Rotation speed is low.
Unusual noise is heard around ring gear.
Pinion returns halfway.
Unusual noise is heard around relay and engine does not rotate.
Voltage (20 – 30 V) between battery relay terminal B and termi-
nal E is not found.
When terminal B and terminal C of starting switch are connected,
engine cranks.
When terminal B at safety relay outlet and terminal C are con-
nected, engine cranks.
Even if terminal B at safety relay outlet and terminal C are con-
nected, engine will not crank.
When terminal at safety switch and terminal B at starting motor
are connected, engine cranks.
SEN06140-00
Cause
E E
Q Q
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Q Q
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Q Q Q
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q
Remedy
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Q
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7
40-600