Isuzu KB P190. Manual — part 383

ENGINE COOLING (4JK1/4JJ1) 6B-9

Inspection and Repair

The water pump is not disassembled type.

Make necessary parts replacement if extreme wear or
damage is found during inspection. Should any of the
following problems occur, the entire water pump
assembly must be replaced.

• Cracks in the water pump body.
• Coolant leakage from the sealed unit.
• Excessive radial play or abnormal noise in the fan

center when rotated by hand.

• Excessive thrust play in the fan center (Standard

play: less than 0.2 mm (0.0078 in)).

• Cracks or corrosion in the impeller.

Installation

1. Water Pump

RTW56BSH000201

a. Install the water pump with a new gasket.

b. Tighten bolts and nuts to specified torque.

Water Pump Nut/Bolt Torque:

25 N·m (2.5 kg·m /18 lb ft)

2. Fan Drive Belt and Pulley and Fan and Fan Clutch.

RTW56ASH025401

a. Install the fan drive belt and fan pulley and fan

and fan clutch.

b. Tighten the nuts to specified torque.

Fan Clutch Nut Torque: 8 N·m (0.8 kg·m /69 lb in)

c. Apply tension to the fan drive belt by moving

the generator.

d. Apply a force of 98 N (10 kg/22 lb) to the drive

belt mid-portion to check the drive belt

deflection.

Fan Drive Belt Deflection

mm (in)

New belt

5 - 6 (0.20 – 0.24)

Reuse belt

7 - 8 (0.28 – 0.32)

3. Upper Fan Shroud

4. Water Outlet Pipe.

a. Install the water outlet pipe to the thermostat

housing.

b. Tighten the outlet pipe bolt to specified torque.

Outlet Pipe Bolt Torque:

25 N·m (2.5 kg·m /18 lb ft)

c. Connect the turbocharger-cooling pipe to outlet

pipe.

6B-10 ENGINE COOLING (4JK1/4JJ1)

5. Radiator Upper Hose.

RTW56FSH000101

a. Connect the radiator upper hose to the water

outlet pipe.

b. The knob of clamp shall be directed to

horizontal.

c. Replenish the engine coolant.

6. Install the engine cover.

ENGINE COOLING (4JK1/4JJ1) 6B-11

Thermostat

Read this Section carefully before performing any
removal and installation procedure. This Section gives
you important points as well as the order of operation.
Be sure that you understand everything in this Section
before you begin.

Removal

1. Remove the engine cover.

2. Radiator Upper Hose

a. Partially drain the engine coolant.

b. Remove the radiator upper hose.

c. Remove the engine harness clip.

RTW56FSH000101

3. Water Outlet Pipe

a. Disconnect the turbocharger-cooling pipe from

outlet pipe.

b. Loosen the fixing bolt and remove the water

outlet bolt.

4. Thermostat

Remove the thermostat from the thermostat

housing.

Take care not to damage the thermostat.

RTW56BSH000101

Legend

1. Front

2. Thermostat

3. Jiggle

Valve

Inspection and Repair

Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is
discovered during inspection.

Operating Test of Thermostat

1. Completely submerge the thermostat in water.

2. Heat the water.Stir the water constantly to avoid

direct heat being applied to the thermostat.

3. Check the thermostat initial opening temperature.

Thermostat Initial Opening Temperature

°C (°F)

85 (185)

4. Check the thermostat full opening temperature.

Thermostat Full Opening Temperature

°C (°F)

100 (212)

Valve Lift At Fully Open Position

mm (in)

10 (0.39)

6B-12 ENGINE COOLING (4JK1/4JJ1)

MFW41CSH001401

Legend

1. Wooden

Piece

2. Agitating

Rod

Installation

1. Thermostat

Install the thermostat.

Mount the jiggle valve with the valve facing engine

front.

RTW56BSH000101

Legend

1. Front

2. Thermostat

3. Jiggle

Valve

2. Water Outlet Pipe.

a. Install the water outlet pipe with new gasket to

the thermostat housing.

b. Tighten the outlet pipe bolt to specified torque.

Outlet Pipe Bolt Torque:

25 N·m (2.5 kg·m /18 lb ft)

c. Connect the turbocharger-cooling pipe to outlet

pipe.

d. Install the engine harness clip.

3. Radiator Upper Hose.

RTW56FSH000101

a. Connect the radiator upper hose to the water

outlet pipe.

b. The knob of the clamp should be directed to

the horizontal side.

c. Replenish the engine coolant.

4. Install the engine cover.