Isuzu NHR 4J Series, Workshop Manual

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00 – 4 SERVICE INFORMATION
3. ENGINE TURNS OVER BUT DOES NOT START
Checkpoint Possible cause Correction
Engine stop
mechanism Defective fuel cut solenoid valve Replace the fuel cut solenoid valve
FUEL IS NOT BEING DELIVERED TO THE INJECTION PUMP
Fuel Fuel tank is empty Fill the fuel tank
Fuel piping Clogged or damaged fuel lines. Loose fuel
line connection Repair or replace the fuel lines
Retighten the fuel line connection
Fuel filter overflow valve does not close Repair or replace the fuel filter
overflow valve Fuel filter
Clogged fuel filter element Replace the fuel filter element or the
filter cartridge
Fuel system Air in the fuel system Bleed the air from the fuel system
Fuel feed pump Defective feed pump Repair or replace the feed pump
FUEL IS BEING DELIVERED TO THE INJECTION PUMP
Use of the wrong fuel Use the correct fuel
Water particles in the fuel Change the fuel
Fuel
Fuel system
Air in the injection pump Bleed the air from the fuel system
Injection nozzle sticking Injection nozzle
Injection nozzle injection starting pressure
too low
Improper spray condition Adjust or replace the injection nozzle
Defective fuel injection nozzle resulting in the
fuel drippage after fuel injection Replace the delivery valve
Defective injection pump control rack
operation Repair or replace the injection pump
control rack
Injection pump plunger worn or stuck Replace the injection pump plunger
assembly
Injection pump drive shaft seizure or other
damage Replace the injection drive shaft
Injection pump
Injection pump governor spring seizure Replace the injection pump governor
spring