Komatsu ecot3 PC300LC-8 Shop Manual page 849

40 Troubleshooting
c) Exhaust smoke comes out but engine does not start
(fuel is being injected)
General causes why exhaust smoke comes out but engine does not
start
• Lack of rotating force due to defective electrical system
• Insufficient supply of fuel
• Insufficient intake of air
• Improper selection of fuel
Confirm recent repair history
Degree of use of
Operated for long period
machine
Suddenly failed to start
Non-specified fuel is being used
Replacement of filters has not been carried out according to Operation and Mainte-
nance Manual
Engine oil must be added more frequently
When engine is preheated or when temperature is low, preheating monitor does not
indicate normally (if monitor is installed)
Dust indicator is red (if indicator is installed)
Air breather hole of fuel tank cap is clogged
Rust and water are found when fuel tank is drained
When fuel filter is removed, there is not fuel in it
Fuel is leaking from fuel piping
Starting motor cranks engine slowly
When engine is cranked, abnormal sound is generated around cylinder head
If air bleeding plug of fuel filter is removed, fuel does not flow
While engine is
out
cranked with starting
motor
If spill hose from injector is disconnected, little fuel spills
When exhaust manifold is touched immediately after starting engine, temperature of
some cylinders is low
Inspect air cleaner directly
Inspect dynamic valve system directly
When compression pressure is measured, it is found to be low
When air is bled from fuel system, air comes out
Inspect fuel filter directly
Carry out troubleshooting for "Rail Press (Very) Low Error." See *1 for failure code.
Carry out troubleshooting for "Power Lift Pump Error." See *2 for failure code.
Engine can be started in reduced cylinder mode.
When specific gravity of electrolyte and voltage of battery are measured, they are
low
Coolant temperature gauge does not indicate normally (if coolant temperature
gauge is installed)
When starting switch is turned to HEAT, intake air heater mount does not become
warm
*1: Failure codes [CA559] and [CA2249]
*2: Failure codes [CA2265] and [CA2266]
PC300, 350-8
E
w
w
w
w
w
Q
w
w
Q
q
q
q
Remedy
SEN02634-02
Cause
E E
w Q
Q Q
w
w
w
Q
w
w
w Q
w
w
q
q
q
q
q
q
q
q
9