Isuzu N-Series. Service manual - part 610

6C-10 ENGINE FUEL

FUEL FILTER CARTRIDGE

Removal

• Remove the cartridge using a filter wrench.

Filter wrench: 5-8840-0253-0 (J-22700)

Installation

• Clean the cartridge mounting surface of filter body

so that the cartridge can be securely.
Apply engine oil thinly to new cartridge O-ring.

• To facilitate bleeding, fill the new cartridge with

light oil.

• Tighten the cartridge until O-ring comes in contact

with the sealing, taking care not to spill the light oil.

• Retighten 1/3 — 2/3 using a filter wrench.

Filter wrench: 5-8840-0253-0 (J-22700)

Air Bleeding

• Operate priming pump to send the air in the fuel

system to the injection pump.

• Loosen injection pump bleeding plug, and operate

the priming pump until no bubble is made.

• Tighten the bleeding plug.
• Start the engine, and if it is not started in 10 sec-

onds or less, repeat the bleeding steps.

• Make sure of no fuel leakage, and tighten the prim-

ing pump.

Draining

• When the water in the sedimentor reaches the

specified volume, warning light is actuated.
In this case, follow the draining steps below.

• Set a vinyl hose over the drain plug.
• Loosen the drain plug.
• To drain the water, operate the priming pump sev-

eral times.

• After draining, tighten the drain plug.

• Operate the priming pump several times to check

for fuel leakage.

• Check and see the warning light is off.

N6A3399E

N6A3012E

ENGINE FUEL 6C-11

FUEL FILTER ASSEMBLY (4JH1-TC)

Components

Removal

1. Remove the filler cap.
2. Remove the fuel sedimenter connector and fuel

heater connector.

3. Remove the feed hose and the return hose from

the fuel filter and plug it so that the fuel does not
flow out.

4. Remove the bolts for mounting the fuel filter.
5. Remove the fuel filter assembly.

Installation

1. Install the fuel filter assembly.
2. Install the bolts for mounting the fuel filter.
3. Install the feed hose and the return hose.
4. Install the fuel sedimenter and fuel heater connec-

tor.

5. Install the filler cap.
6. Bleed out the air.

• Refer to “Fuel Filter Cartridge (4JH1-TC)”.

Legend

1. Filler Cap

4. Fuel Heater Connector

2. Fuel Sedimenter Connector

5. Bolt

3. Fuel Hose

6. Fuel Filter Assembly

N6A1605E

6

4

3

5

2

6C-12 ENGINE FUEL

FUEL FILTER CARTRIDGE (4JH1-TC)

Removal

1. Remove the cartridge using the filter wrench.

Filter wrench: J-22700

2. Remove the sedimenter sensor.

Installation

1. Assemble the sedimenter sensor in the new car-

tridge.

2. Clean the cartridge mounting surface in the filter

body so that the cartridge can be seated securely.

3. Coat a thin layer of engine oil on the O-ring in the

new cartridge.

4. To simplify air bleed, fill light oil on the new car-

tridge.

5. Tighten the cartridge until the O-ring touches the

sealing surface. During this process take adequate
care that the light oil that is inside does not flow out.

6. Use the filter wrench and tighten rotating by 1/3 to

2/3.
Filter wrench: J-22700

Injection Pump Air Bleeding (4JH1-TC)

Injection pump air bleeding is required to start the en-
gine when —

• The fuel supply has been exhausted (running out

of gas).

• The fuel filter has been replaced.
• The injection pump has been replaced.

Caution:
If the injection pump has been replaced, the air bleeding
procedure will require more time and effort (this is be-
cause there is no fuel in the pump).

1. Loosen the air bleed nut on the priming pump

plunger (at the top of the fuel filter).

2. Move the priming pump plunger up-and-down until

strong resistance is felt (about 15 cycles).

3. Stop pumping and tighten the air bleed nut.
4. Wait for 1 minute.
5. Loosen the air bleed nut on the priming pump

plunger again.

6. Move the priming pump plunger up-and-down until

strong resistance if felt (about 10 cycles).

7. Stop pumping and tighten the air bleed nut.
8. Wait for 1 minute.
9. Loosen the air bleed nut on the priming pump

plunger again.

10. Move the priming pump plunger up-and-down until

strong resistance is felt (about 5 cycles).

11. Stop pumping and tighten the air bleed nut.
12. Press the accelerator and clutch pedals all the way

to the floor and hold them down. Turn the ignition
switch to the ON position. Wait until the glow indi-
cator lamp turns on and off.

Legend

1. O-ring
2. Cartridge
3. Sendimenter Sensor
4. Fuel Heater Connector

N6A1606E

N6A1607E

ENGINE FUEL 6C-13

Caution:
If the engine is cold, the glow indicator light will stay on
for 4 — 7 seconds before turning off.
However, if the engine is hot, the lamp will not turn on.
13. Turn the ignition switch to the START position and

crank the engine until it starts (do not crank the en-
gine for more than 10 seconds).
If the engine does not start, repeat Steps 9 — 13.

14. Allow the engine to idle for 5 minutes.

Water drain

A warning lamp will light up if water above the specified
volume collects in the sedimenter. In such cases, drain
out the water by performing the following operations:

• Set a container at the tip of the plastic hose.
• Loosen the drain plug.
• Operate the priming pump several times to dis-

charge the water.

• Tighten the drain plug after discharging the water.
• Operate the priming pump several times and check

for fuel leakage.

• Check that the warning lamp in the meter is off.

Special Tools

Illustration

Tool Number / 

Description

J-22700

Filter wrench

5884002530