Nissan Frontier. Manual - part 219

THERMOSTAT AND THERMOSTAT HOUSING

CO-23

< REMOVAL AND INSTALLATION >

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THERMOSTAT AND THERMOSTAT HOUSING

Exploded View

INFOID:0000000009478169

Removal and Installation Thermostat

INFOID:0000000009478170

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 the radiator. Refer to 

CO-12, "Changing Engine Coolant"

.

CAUTION:

• Perform this step when the engine is cold.

• Do not spill engine coolant on drive belt.

2. Remove the air duct. Refer to 

EM-25, "Exploded View"

.

3. Disconnect radiator hose (lower) at water inlet side. Refer to 

CO-16, "Exploded View"

.

4. Remove water inlet, O-ring and thermostat.

CAUTION:

Do not reuse O-rings.

1.

Gasket

2.

Water outlet

3.

Water pump pulley

4.

Water pump

5.

Thermostat

6.

O-ring

7.

Water inlet

8.

Water pump and thermostat housing 9.

Heater pipe

10. Water hose

11. Water hose

12. Heater outlet

13. Engine coolant temperature sensor

14. Water control valve

A.

To heater

B.

To electric throttle control actuator

C.

To oil cooler

Front

AWBIA0868GB

CO-24

< REMOVAL AND INSTALLATION >

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THERMOSTAT AND THERMOSTAT HOUSING

INSPECTION AFTER REMOVAL

• Place a thread so that it is caught in the valve of the thermostat.

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 tempera-

ture and check the valve closing temperature. 

If out of the specification range, replace the thermostat. 

INSTALLATION

Installation is in the reverse order of removal.

• Apply a mild soap to a new O-ring before inserting heater pipe end into water pump and thermostat housing.

Then insert it immediately.

Thermostat

• Install thermostat by making O-ring (1) groove fit to thermostat

flange (A) around the whole circumference.

CAUTION:

Do not reuse O-ring.

• Install thermostat with jiggle valve (A) facing upward. The position

may deviate within the range of 20

° (b).

INSPECTION AFTER INSTALLATION

• Check for engine coolant leaks. Refer to 

CO-11, "System Inspection"

.

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

Removal and Installation Thermostat Housing

INFOID:0000000009478171

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:

SLC252B

Thermostat

Standard

Valve opening temperature

Refer to 

CO-30, "Standard and Limit"

Full-open lift amount

Refer to 

CO-30, "Standard and Limit"

Valve closing temperature

Refer to 

CO-30, "Standard and Limit"

PBIC3317J

JPBIA2314ZZ

THERMOSTAT AND THERMOSTAT HOUSING

CO-25

< REMOVAL AND INSTALLATION >

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

ing.

REMOVAL

1. Remove water pump. Refer to 

CO-21

. 

2. Remove thermostat. Refer to 

CO-23, "Removal and Installation Thermostat"

.

3. Remove the radiator hose (upper) from the radiator.
4. Remove exhaust manifold cover. Refer to 

EM-31, "Exploded View"

.

5. Remove oil level gauge and oil level gauge guide. Refer to 

EM-80, "Exploded View"

.

CAUTION:

Plug the oil level gauge guide opening to prevent foreign materials from entering oil pan.

6. Remove A/C compressor without disconnecting the A/C hoses and position aside. Refer to 

HA-25,

"Removal and Installation for Compressor"

.

7. Disconnect electric throttle control actuator, oil cooler and heater hose from heater pipe.
8. Remove bolt for heater pipe at water pump and thermostat housing.
9. Disconnect heater pipe from water pump and thermostat housing.
10. Remove water pump and thermostat housing. 

CAUTION:

• Do not reuse O-ring.

• Do not reuse gasket.

INSTALLATION

Installation is in the reverse order of removal.

• Apply a mild soap to O-ring before inserting heater pipe end into water pump and thermostat housing. Then

insert it immediately.

CAUTION:

Do not reuse O-ring.

INSPECTION AFTER INSTALLATION

• Check for engine coolant leaks. Refer to 

CO-11, "System Inspection"

.

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

CO-26

< REMOVAL AND INSTALLATION >

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WATER CONTROL VALVE

WATER CONTROL VALVE

Exploded View

INFOID:0000000009478172

Removal and Installation

INFOID:0000000009478173

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

CAUTION:

Perform when the engine is cold.
1. Remove air ducts and resonator assembly.
2. Partially drain the engine coolant from the radiator. Refer to 

CO-12, "Changing Engine Coolant"

.

3. Remove radiator hose (upper) from the water outlet.
4. Remove the heater outlet.
5. Remove the water control valve.

INSPECTION AFTER REMOVAL

1.

Gasket

2.

Water outlet

3.

Water pump pulley

4.

Water pump

5.

Thermostat

6.

O-ring

7.

Water inlet

8.

Water pump and thermostat housing 9.

Heater pipe

10. Water hose

11. Water hose

12. Heater outlet

13. Engine coolant temperature sensor

14. Water control valve

A.

To heater

B.

To electric throttle control actuator

C.

To oil cooler

Front

AWBIA0868GB