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Service Manual Mitsubishi L-Series diesel engines
Version 08/2004
ENGLISH
TROUBLESHOOTING GENERAL
6.2 Hard starting
6.2.1 Matters to be checked before
diagnosis
1. Clogging of the air cleaner
2. Coagulation of engine oil
3. Use of poor-quality fuel
4. Lowering of cranking speed
6.2.2 Diagnosis
Does preheating system
operate properly?
No Z
Does current flow in glow plug
circuit as soon as key switch is
turned to ‘H’ (ON)?
No Z
Inspect key switch, wiring and
glow indicator.
V
V Yes Yes Z Inspect glow plug.
Is electric wiring normal?
Does fuel feed pump, if provided operate when key switch is turned ON?
No Z
Inspect fuel pump and/or
wiring.
V Yes
Does fuel flow in fuel line? No Z
Does fuel flow out when fuel
injection pump air vent screw is
loosened?
No Z
Inspect fuel filter, fuel pipe and
fuel tank.
V Yes
Is engine in good order?
(Injection timing and valve timing)
No Z Adjust engine properly.
V Yes
Do injection nozzles operate properly?
State of fuel spray and injection starting pressure.
No Z Inspect injection nozzles.
V Yes
Is cylinder compression pressure proper? No Z
Inspect valves, pistons, piston
rings and cylinder head
gasket.
V Yes
Inspect injection pump.