10.3.6. Diagnostics and troubleshooting
- 156 -
Complaints Possible causes Corrections
1. Engine won’t start
•
Fuel pipes clogged or air into Correct
1) Fuel not being pumped pipe fine
out from feed pump
•
Feed pump valve defective Replace
•
Feed pump piston or Push rod Disassemble, correct
sticking
2) Fuel not being injected
•
Fuel filter element restricted Clean
from injection pump
•
Air in fuel filter or injection Bleed
pump
•
Plunger and/or delivery valve Disassemble, correct
sticking or defective
3) Fuel injection timing
•
Injection pump not properly Check, correct
Incorrect installed on pump bracket
•
Injection pump tappet Check, correct
incorrectly adjusted
•
Cams on cam shaft worn Replace
excessively
4) Injection nozzles
•
Needle valves sticking Correct or replace
inoperative
•
Fuel leaking past clearance Correct or replace
between nozzle and needle
valve
•
injection pressure incorrect Adjust
2. Engine starts but stalls
•
Pipe from feed pump to injection
Clean
immediately pump clogged or filter clogged
•
Air in fuel Bleed
•
Feed pump delivery insufficient Disassemble, correct
•
Fuel delivery insufficient due to Replace breather
clogging of fuel tank air breather
3. Engine lacks power
•
Plunger worn excessively Replace
•
Injection timing incorrect Adjust
•
Delivery valves defective Replace
•
Nozzle leaks excessively Correct or replace
•
Nozzle not working normally Disassemble, correct
4. Engine knocking
•
Injection timing too fast Adjust
•
Nozzle injection pressure too Adjust
high
•
Nozzles not working normally Disassemble, correct
5.
Engine knocks seriously
•
Injection timing incorrect Adjust
producing excessive
•
Nozzle injection pressure too low
Adjust
exhaust smoke
•
Nozzle spring broken Replace
•
Nozzles not working normally Replace
•
Plungers worn excessively Adjust
•
Delivery valves seat defective Replace
•
Supply of fuel excessively Check feed pump
To Next Page
