Isuzu N-Series. Manual - part 624

6C-66 ENGINE FUEL

Engine ; 4JB1-TC
Injection pump identification No. ; 104746-6601
Adjustment specification of injection volume

Adjustment specification of timer and pump case pressure

Pump rotation

(rpm)

Average 

injection quantity

(mm

3

/ST)

Uneven 

amplitude
(mm

3

/ST)

Boost pressure 

(kPa (kg/cm

2

))

Oil temperature

(

°C)

Remarks

500

60.5

±1.0

5.0

0

48

±2

Standard

800

67.4

±1.0

5.5

52.0 (0.531)

50

±2

Standard

800

76.8

±1.0

6.0

80.0 (0.821)

50

±2

Standard

1000

(83.8

±6.5)

80.0 (0.821)

50

±2

1250

(91.5

±6.5)

80.0 (0.821)

50

±2

1700

(105.7

±6.5)

80.0 (0.821)

50

±2

2075

34.0

±3.0

7.0

80.0 (0.821)

52

±2

Standard

375

13.9

±2.0

2.0

0

48

±2

Standard

100

60 

+40

-0

0

48

±2

N6A3625E

Pump rotation

(rpm)

Timer piston stroke 

(mm)

At pressure of pump

(MPa (kg/cm

2

))

Boost Pressure

(kPa (kg/cm

2

))

Remarks

1020

Below 0.5

80.0 (0.82)

1350

1.8

±0.2

471

±29 (4.8±0.3)

80.0 (0.82)

Standard

1500

(3.0

±0.4)

80.0 (0.82)

1800

4.5 

+0.4

 -0.3

80.0 (0.82)

ENGINE FUEL 6C-67

Potentiometer adjustment

N6A3626E

Pump speed

(r/min)

Out-put voltage

(V)

Average injection 

quantity

(mm

3

/st)

BoostPressure

(kPa (kg/cm

2

))

Remarks

1080

3.56

±0.03

27.5

±2.0

0

Standard

375

(0.93

±0.45)

13.9

±2.0

0

Standard

N6A3622E

6C-68 ENGINE FUEL

FUEL TANK

Component

Legend

1. Evaporator fuel hose

5. Band

2. Fuel feed hose

6. Fuel tank

3. Fuel return hose

7. Frame

4. Fuel gauge unit connector

N6A3472E

ENGINE FUEL 6C-69

Removal

Preparation:

• Disconnect battery ground cable.
• Loosen fuel filler cap.
• Drain fuel from drain plug.
• After the drain fuel, tighten the drain plug to the

specified torque.

Tighten:
29 N

⋅m(3 kg⋅m/22 lb⋅ft)

1. Evaporator Fuel Hose
2. Fuel Feed Hose
3. Fuel Return Hose

• Plug the hose to prevent fuel from getting spilt, and

tie it to the frame with the plugged end up.

4. Fuel Gauge Unit Connector

• Remove the connector of the fuel gauge.

5. Band

• Remove the nut of the fuel tank fixing band, and

then remove the band end on the frame side.

6. Fuel Tank

• Pull out the fuel tank to the outside.

Notice:
When it is not possible to pull out the fuel tank, remove
the bracket and then draw out the fuel tank downward.

Installation

1. Fuel Tank

Notice:
When the bracket was removed to take off the fuel tank,
install the bracket to the frame and tighten it to the spec-
ified torque.

Tighten:
55 N

⋅m(5.6 kg⋅m/41 lb⋅ft)

When mounting the fuel tank on the bracket, be sure to
place the packing section pasted on the fuel tank se-
curely on the bracket.

2. Band

• Tighten the band to the specified torque.

Tighten:
12 N

⋅m(1.2 kg⋅m/104 lb⋅ft)

3. Fuel Gauge Unit Connector

• Connect the fuel gauge unit connector.

4. Fuel Return Hose
5. Fuel Feed Hose

• Set the hose to the pipe more than 25 mm (0.98 in)

deep.

6. Evaporator Fuel Hose

• Fill the fuel to the fuel tank.
• Connect battery ground cable.