S-4 Engine Stops During Operations - Komatsu WA250-6 Shop Manual

600 Troubleshooting of engine (S-mode)

S-4 Engine stops during operations

S-4 Engine stops during operations
General causes why engine stops during operations
Internal parts of engine seized
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Insufficient supply of fuel
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There is overheating
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Problem in hydraulic pump
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Confirm recent repair history
Degree of use of machine
Condition when engine
stopped
Non-specified fuel is being used
Replacement of filters has not been carried out according to Operation
and Maintenance Manual
Fuel level monitor indicates low level
When fuel tank is inspected, it is found to be empty
Air breather hole of fuel tank cap is clogged
Fuel is leaking from fuel piping
Rust and water are found when fuel tank is drained
Metal particles are found when oil pan is drained
When engine is cranked by
hand
Engine turns, but stops when load is applied to machine
Inspect dynamic valve system directly
Inspect piston, connecting rod directly
Inspect crankshaft bearing directly
Inspect gear train directly
Inspect fuel filter, strainer directly
Inspect feed pump gauze filter directly
Inspect feed pump directly
Carry out troubleshooting according to "No-pressure feed by supply
pump (*1)" in display of code
Engine rotates when pump auxiliary equipment (pump, compressor, etc.)
is removed
Check controller power supply wiring
Check starting switch wiring
*1: Failure codes [CA559] and [CA2249] in the display of code
WA250, 250PZ-6
Operated for long period
Abnormal noise was heard and engine
stopped suddenly
Engine overheated and stopped
Engine stopped slowly
There was hunting and engine stopped
Does not turn at all
Turns in opposite direction
Moves by amount of gear backlash
Supply pump shaft does not turn
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Remedy
SEN03850-00
Causes
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40-600
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11