Yanmar 3JH4E Service Manual page 131

(I) Amount of oil supply from fuel
injection pump inadequate
(V) Irregular fuel
(I) Amount of oil supply from fuel injection pump inadequate
No.
1 Worn plunger.
2 Sticking of plunger.
3 Oil leakage from exhaust valve.
4 Oil leakage from joint of high pressure pipe.
5 Faulty adjustment of fuel pump.
6 Inaccurate positioning of adjustment rack.
7 Clogging of fuel filter.
8 Clogging of fuel oil pipe.
9 Damaged valve spring.
10 Faulty supply pump.
(II) Amount of fuel injection inadequate
No.
1 Clogging of nozzle hole.
2 Faulty valve seat.
3 Sticking of valve needle.
4 Loose high pressure pipe.
5 Worn valve needle.
6 Clogging of filter.
(III) Faulty governor
No.
1 Damaged governor bearing.
2 Inaccurate length of governor link.
INSUFFICIENT POWER OUTPUT
(II) Amount of fuel injection
inadequate
injection timing
Cause and effect
Cause and effect
Cause and effect
(III) Faulty governor
(VI) Clogged intake (VII) Miscellaneous
air filter
Replace.
Disassemble and repair or replace.
Lap valves.
Tighten firmly.
Adjust.
Adjust.
Clean.
Clean.
Replace.
Repair.
Clean nozzle hole or replace.
Lap or replace.
Lap or replace.
Tighten firmly.
Replace.
Clean.
Replace.
Repair.
111
3. Troubleshooting
(IV) Leakage of pressurized
gas from inside cylinder
Countermeasure
Countermeasure
Countermeasure