Nissan Frontier. Manual - part 227

WATER INLET AND THERMOSTAT ASSEMBLY

CO-55

< REMOVAL AND INSTALLATION >

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WATER INLET AND THERMOSTAT ASSEMBLY

Exploded View

INFOID:0000000009478193

Removal and Installation

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WARNING:

Do not remove the radiator cap when the engine is hot. Serious burns could occur from high pressure

engine coolant escaping from the radiator. Wrap a thick cloth around the cap. Slowly turn it a quarter

of a turn to release built-up pressure. Carefully remove radiator cap by turning it all the way.

NOTE:

When removing components such as hoses, tubes/lines, etc., cap or plug openings to prevent fluid from spill-

ing.

REMOVAL

1. Remove engine cooling fan (Motor driven type). Refer to 

CO-48, "Removal and Installation (Motor driven

type)"

2. Disconnect radiator hose (lower) and oil cooler hose from water inlet and thermostat assembly.
3. Remove water inlet and thermostat assembly.

CAUTION:

• Do not disassemble water inlet and thermostat assembly. 

• Replace water inlet and thermostat assembly as a unit.

INSPECTION AFTER REMOVAL

1. Check valve seating condition at room temperature. It should seat tightly.

1.

Water inlet and thermostat assembly 2.

Gasket

PBIC2839E

SLC962AB

CO-56

< REMOVAL AND INSTALLATION >

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WATER INLET AND THERMOSTAT ASSEMBLY

2. Check valve operation.

• Place a thread so that it is caught in the valve of the thermo-

stat. Immerse fully in a container filled with water. Heat while

stirring.

• The valve opening temperature is the temperature at which

the valve opens and falls from the thread.

• Continue heating. Check the full-open lift amount.

NOTE:

The full-open lift amount standard temperature is the reference

value.

• After checking the full-open lift amount, lower the water tem-

perature and check the valve closing temperature.

If out of the specification range, replace water inlet and thermostat assembly.

INSTALLATION

Installation is in the reverse order of removal.

CAUTION:

Do not spill engine coolant in engine room. Use shop cloth to absorb engine coolant.

INSPECTION AFTER INSTALLATION

• Check for engine coolant leaks. Refer to 

CO-39, "System Inspection"

.

• Start and warm up engine. Visually check for engine coolant leaks. Repair as necessary.

SLC949A

Thermostat

Standard

Valve opening temperature

Refer to 

CO-59, "Standard and Limit"

Full-open lift amount

Refer to 

CO-59, "Standard and Limit"

Valve closing temperature

Refer to 

CO-59, "Standard and Limit"

WATER OUTLET AND WATER PIPING

CO-57

< REMOVAL AND INSTALLATION >

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WATER OUTLET AND WATER PIPING

Exploded View

INFOID:0000000009478195

Removal and Installation

INFOID:0000000009478196

WARNING:

Do not remove the radiator cap when the engine is hot. Serious burns could occur from high pressure

engine coolant escaping from the radiator. Wrap a thick cloth around the cap. Slowly turn it a quarter

of a turn to release built-up pressure. Carefully remove radiator cap by turning it all the way.

NOTE:

When removing components such as hoses, tubes/lines, etc., cap or plug openings to prevent fluid from spill-

ing.

REMOVAL

1. Drain engine coolant from radiator. Refer to 

CO-40, "Changing Engine Coolant"

.

CAUTION:

• Perform this step when engine is cold.

• Do not spill engine coolant on drive belts.

2. Remove the intake manifold collector. Refer to 

EM-142, "Removal and Installation"

.

3. Remove engine coolant temperature sensor as necessary.

CAUTION:

Be careful not to damage engine coolant temperature sensor.

4. Remove water outlet, heater pipe, water bypass hoses and water pipe.

INSTALLATION

1.

Engine coolant temperature sensor

2.

Washer

3.

Water outlet

4.

Heater hose

5.

O-ring

6.

Water pipe

7.

Water hose

8.

Radiator hose (upper)

9.

Water hose

10. Water hose

11. Gasket

12. Heater pipe

13. Heater hose

14. Gasket

WBIA0615E

CO-58

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WATER OUTLET AND WATER PIPING

Installation is in the reverse order of removal, paying attention to the following.

• Securely insert each hose, and install clamp at a position where it does not interfere with the pipe bulge.

• Before inserting water pipe into water outlet, apply mild soap to O-ring.

CAUTION:

Do not reuse O-ring.

INSPECTION AFTER INSTALLATION

• Check for engine coolant leaks. Refer to 

CO-39, "System Inspection"

.

• Start and warm up engine. Visually check for engine coolant leaks. Repair as necessary.