Fuel Consumption Is Excessive - Komatsu ecot3 PC300LC-8 Shop Manual

40 Troubleshooting
S-10 Fuel consumption is excessive
General causes why fuel consumption is excessive
• Leakage of fuel
• Defective condition of fuel injection (fuel pressure, injection timing)
• Excessive injection of fuel
Confirm recent repair history
Degree of use of
Operated for long period
machine
More than for other machines of same model
Condition of fuel
Gradually increased
consumption
Suddenly increased
There is external leakage of fuel from engine
Combustion is irregular
Engine oil level rises and oil smells of diesel fuel
When exhaust manifold is touched immediately after starting engine, temperature of some cylin-
ders is low
Low idle speed is high
Torque converter stall occurred or pump relief speed is high
Black
Color of exhaust
gas
White
Remove and inspect head cover directly
Inspect feed pump oil seal directly
Carry out troubleshooting for "Rail Press (Very) Low Error." See *1 for failure code.
When a cylinder is cut out for reduced cylinder mode operation, engine speed does not change
If spill tube from injector is disconnected, much fuel spills
Carry out troubleshooting for "Coolant Temp Sens High (Low) Error." See *2 for failure code.
Check with monitoring function of the machine monitor.
*1: Failure codes [CA559] and [CA2249]
*2: Failure codes [CA144] and [CA145]
PC300, 350-8
SEN02634-02
Cause
E E
Q
Q
Q Q
w
w w
Q Q
Q
q
q
q
q
Remedy
1
E
Q Q Q
Q
w
w
Q
Q
Q Q
q
q
q
q
17