Komatsu GD555-5 Operation & Maintenance Manual page 244

OPERATION
Problem
Does not reach rated speed when
there is load
Main causes
Defective actuation of tachometer
Lack of fuel
Air in fuel line
Defective fuel supply pump,
nozzle
Clogged fuel filter
Output of variable output selector
signal not given
Oil level too high
Clogged air cleaner
Leakage of intake or exhaust
from turbocharger
Use of poor quality fuel
Defective thermostat
TROUBLESHOOTING
Remedy
( Check, replace)
Add fuel. See CHECK
BEFORE STARTING
( Repair location of air entry)
( Replace)
Replace filter
( Replace transmission
controller)
Adjust to correct level
Clean, replace
( Check, repair, replace)
Change fuel
( Replace)
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