Isuzu N-Series. Manual — part 547
SERVICE INFORMATION 00-3
3. Engine Turns Over But Does Not Start
4. Quick-On Start System
Preparation
1. Disconnect the thermoswitch connector.
2. Determine whether or not the glow plugs are receiving power.
a. Make sure that the starter switch is “OFF”.
b. Connect a voltmeter between one of the glow plugs and the cylinder wall.
c. Move the starter switch to the “ON” position.
The voltmeter needle will show the souse voltage (12V) if the glow plugs are receiving power.
If the voltmeter needle does not move, the glow plugs are not receiving power.
3. Perform the troubleshooting procedure.
Checkpoint
Possible cause
Correction
Engine stop mecha-
nism
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
Fuel filter overflow valve does not close
Repair or replace the fuel filter overflow
valve
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
Fuel
Use of the wrong fuel
Use the correct fuel
Water particles in the fuel
Change the fuel
Fuel system
Air in the injection pump
Bleed the air from the fuel system
Injection nozzle
Injection nozzle sticking
Injection nozzle injection starting pressure
too low
Improper spray condition
Adjust or replace the injection nozzle
Injection pump
Defective fuel injection nozzle resulting in
the fuel drippage after fuel injection
Replace the delivery valve
Defective injection pump control rack oper-
ation
Repair or replace the injection pump con-
trol 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 governor spring seizure
Replace the injection pump governor
spring
00-4 SERVICE INFORMATION
* When being normal temperature, the indicator lamp of 4JH1TC is not turn on.
Checkpoint
Possible cause
Correction
Glow Plugs are Receiving Power
Glow plug indicator
light does not turn on
Defective indicator light bulb
Replace the indicator light bulb
Quick-on start timer
Defective quick-on start timer
Replace the quick-on start timer
Glow plug indicator
light turns on the 0.3
seconds
Defective quick-on start timer
Replace the quick-on start timer
Glow plug indicator
light turns on for 3.5
seconds
Return the starter switch to the “ON” posi-
tion from the “START” position after the
engine starts if the glow plug relay remains
on less than 14 seconds, the quick-on start
timer is defective
Replace the quick-on start timer
Move the starter switch from the “OFF”
position to the “ON” position if the glow
plug relay remains on less than 14 sec-
onds, the quick-on start timer is defective
Replace the quick-on start timer
Thermo switch
Defective thermo switch
Replace the thermo switch
Glow plug continuity
No glow plug continuity
Replace the glow plugs
Glow Plugs are not Receiving Power
Glow plug indicator
light does not turn on
Broken indicator light fuse
Replace the fuse
Quick-on start timer
Defective quick-on start timer
Replace the quick-on start timer
Glow plug indicator
light turns on for 3.5
seconds
Defective glow plug relay
The glow plug relay does not turn on after
the starter switch is moved from the “OFF”
position to the “ON” position
Replace the glow plug relay
Defective quick-on start timer
Replace the quick-on start timer
Defective glow plug relay wiring harness
Repair or replace the wiring harness
Defective fusible link or wiring harness
The glow plug relay turns on when the
starter switch is moved from the “OFF”
position to the “ON” position
Replace the fusible link or the wiring har-
ness
SERVICE INFORMATION 00-5
Unstable Idling
*The adjustment of the position which is related to the injection pump is unnecessary for 4JH1TC by the adoption of
the electronic control injection pump.
Checkpoint
Possible cause
Correction
Idling system
Idling improperly adjusted
Adjust the idling
Fast idling speed
Defective fast idling speed control device
Repair or replace the fast idling speed
control device
Accelerator control
system
Accelerator control system improperly
adjusted
Adjust the accelerator control system
Fuel system
Fuel system leakage or blockage
Repair or replace the fuel system
Air in the fuel system
Bleed the air from the fuel system
Water particles in the fuel system
Change the fuel
Fuel filter
Clogged fuel filter element
Replace the fuel filter element or the fuel
filter cartridge
Fuel feed pump
Defective fuel feed pump
Repair or replace the fuel feed pump
Injection nozzle
Injection nozzle sticking
Replace the injection nozzle
Injection nozzle injection starting pressure
too low
Improper spray condition
Adjust or replace the injection nozzle
Injection pump
Defective delivery valve resulting in fuel
drippage after fuel injection
Replace the delivery valve
Injection timing improperly adjusted
Adjust the injection timing
Insufficient injection volume
Adjust the injection volume
Defective idle spring
Replace the idle spring
Defective governor lever operation
Repair or replace the governor lever
Regulator valve improperly adjustment
Adjust or replace the regulator valve
Broken plunger spring
Replace the plunger spring
Worn plunger
Replace the plunger assembly
Worn cam disc
Replace the cam disc
Valve clearance
Valve clearance improperly adjusted
Adjust the valve clearance
Compression pressure
Blown out cylinder head gasket. Worn cyl-
inder liner.
Piston ring sticking
Replace the related parts
00-6 SERVICE INFORMATION
Insufficient Power
Checkpoint
Possible cause
Correction
Air cleaner
Clogged air cleaner element
Clean or replace the air cleaner element
Fuel
Water particle in the fuel
Replace fuel
Fuel filter
Clogged fuel filter element
Replace the fuel filter element or the fuel
filter cartridge
Fuel feed pump
Defective fuel feed pump
Repair or replace the fuel feed pump
Injection nozzle
Injection nozzle sticking
Replace the injection nozzle
Injection nozzle injection starting pressure
too low
Improper spray condition
Adjust or replace the injection nozzle
Fuel injection pipes
Fuel injection pipes damaged or
obstructed
Replace the fuel injection pipes
Injection pump
Defective regulating valve
Repair or replace the regulating valve
Defective delivery valve
Replace the delivery valve
Defective timer
Repair or replace the timer
Worn cam disc
Replace the cam disc
Improper control lever operation
Adjust or replace the control lever
Defective injection timing
Adjust the injection timing
Repair or replace the injection pump timer
Weak governor spring
Replace the governor spring
Worn plunger
Replace the plunger assembly
Compression pressure
Blown out cylinder head gasket. Worn cyl-
inder liner.
Piston ring sticking
Replace the related parts
Valve clearance
Valve clearance improperly adjusted
Adjust the valve clearance
Valve spring
Valve spring weak or broken
Replace the valve spring
Exhaust system
Exhaust pipe clogged
Clean the exhaust pipe
Full load adjusting
screw seal
Open and improperly set adjusting screw
seal
Adjust and reseal the adjusting screw
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст