Service manual

FUEL SYSTEM TROUBLESHOOTING
PROBLEM PROBABLE CAUSE
VERIFICATION/REMEDY
Engine hard to start or
fails to start
1. No fuel at injectors.
1. Check causes a through e.
a. No fuel in fuel tank and/or fuel shut off.
a. Fill tank. Open shutoff and bleed system.
b. Fuel filter clogged.
b. Replace filter and bleed.
c. Fuel filter clogged.
c. Bleed pump. Check fittings for suction leak
on fuel supply.
d. Fuel shutoff solenoid not working.
d. Trouble shoot as described in previous section.
e. Injection pump faulty.
e. Inspect pump. Repair or replace pump as needed.
2. Fuel injectors faulty.
2. Remove and test nozzles. Repair nozzles as needed
3. Water and/or air in fuel filters.
3. Remove water and/or bleed air from system. Check
system for leaks and fuel tank for water contamination.
4. Injection timing incorrect.
4. Check and adjust the timing.
5. Glow plugs not working.
5. Check glow plug circuit and repair as needed.
Engine idling too low. 1. Idle speed too low.
1. Adjust idle stop as needed.
2. Fuel filter clogged.
2. Replace filter and bleed fuel system.
3. Incorrect injection pump timing.
3. Check timing and adjust as needed.
4. High pressure injection line leaking.
4. Slacken attaching nut and retighten.
5. Fuel injector leaking at sealing gasket in head.
5. Retighten injector and/or replace sealing washer.
6. Injection nozzle not operating properly.
6. Check nozzle and adjust as needed.
7. Engine air intake obstructed.
7. Check air flow intake silencer and air flow into engine
compartment.
Fuel consumption too high. 1. Idle speed too high.
1. Check engine speed.
2. Engine air intake restricted.
2. Check intake and correct.
3. Injection timing incorrect.
3. Check timing and readjust pump as needed.
4. Injector nozzle leaking.
4. Tighten nozzle or replace sealing gasket.
5. Injector not operating properly.
5. Remove injector and adjust nozzle spray pressure.
6. Engine overloaded.
6. Check propeller size and engine performance
(continued)
Engines
& Generators
36