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Service Manual Mitsubishi L-Series diesel engines
Version 08/2004
TROUBLESHOOTING
ENGLISH
GENERAL
6.5 Black-smoky exhaust
6.5.1 Matters to be checked before
diagnosis
1. Clogging of air cleaner element
2. Use of poor-quality fuel
3. Overload
6.5.2 Diagnosis
Is smoke set of injection pump correct? No Z Adjust smoke set.
V Yes
Is engine adjusted properly?
(Check for excessive valve clearance and improper injection timing.)
No Z Adjust engine.
V Yes
Do injection nozzles operate properly?
(Check for improper shape of fuel spray and for excessively high injection
starting pressure.)
No Z Inspect injection nozzles.
V Yes
Is cylinder compression proper? No Z
Inspect valves, cylinder head
gasket, pistons, and piston
rings.
V Yes
Inspect injection pump.