Infiniti G37 Coupe. Manual - part 342

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COOLING FAN

ASSEMBLY

Note the following, and assemble in the reverse order of disassembly.

CAUTION:

RH and LH cooling fans are different. Be careful not to misassemble them.
• Install each fan in the following position.

• Secure the harness tightly to the fan shroud to prevent the fan rotation area from being loose.

Inspection

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INSPECTION AFTER REMOVAL

Check that fan motors operate normally.
NOTE:
Cooling fans are controlled by cooling fan control module. For details, refer to 

EC-73, "Component Parts Loca-

tion"

.

INSPECTION AFTER DISASSEMBLY

Cooling Fan

Inspect cooling fan for crack or unusual bend.
• If anything is found, replace cooling fan.

Right side

: 9 blades

Left side

: 11 blades

WATER PUMP

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WATER PUMP

Exploded View

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Removal and Installation

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CAUTION:

• When removing water pump assembly, be careful not to get engine coolant on drive belts.
• Water pump cannot be disassembled and should be replaced as a unit.
• After installing water pump, connect hose and clamp securely, then check for leaks using the radia-

tor cap tester (commercial service tool) and the radiator cap tester adapter [SST: EG17650301
(J33984-A)].

REMOVAL

1.

Remove engine cover. Refer to

EM-24, "Exploded View"

. 

2.

Release the fuel pressure. Refer to 

EC-601, "Inspection"

.

3.

Disconnect the battery cable from the negative terminal.

4.

Remove air duct and air cleaner case assembly (RH and LH). Refer to 

EM-26, "Exploded View"

.

5.

Remove reservoir tank. Refer to 

CO-14, "Exploded View"

.

6.

Separate engine harness removing their brackets from front timing chain case.

7.

Remove engine undercover with power tool.

8.

Drain engine oil. Refer to 

LU-7, "Draining"

.

CAUTION:

• Perform this step when the engine is cold.
• Never spill engine oil on drive belts.

9.

Drain engine coolant from radiator. Refer to 

CO-8, "Draining"

.

CAUTION:

• Perform this step when the engine is cold.
• Never spill engine coolant on drive belts.

10. Remove cooling fan assembly. Refer to 

CO-17, "Exploded View"

.

11. Remove radiator hose (upper and lower). Refer to 

CO-14, "Exploded View"

.

12. Remove front timing chain case. Refer to 

EM-48, "Exploded View"

.

13. Remove timing chain tensioner (primary) as follows:

1.

Timing chain tensioner (primary)

2.

Water pump

3.

O-ring

4.

O-ring

A.

Identify with yellow paint mark

B.

Identify with light blue paint mark
Apply engine coolant

Refer to 

GI-4, "Components"

 for symbols in the figure.

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WATER PUMP

a.

Remove lower mounting bolt (1).

b.

Loosen upper mounting bolt (2) slowly, and then turn chain ten-
sioner (primary) (3) on the upper mounting bolt so that plunger
(4) is fully expanded.
NOTE:
Even if plunger is fully expanded, it is not dropped from the body
of timing chain tensioner (primary).

c.

Remove upper mounting bolt, and then remove timing chain tensioner (primary).

14. Remove water pump as follows:
a.

Remove three water pump mounting bolts. Secure a gap between water pump gear and timing chain, by
turning crankshaft counterclockwise until timing chain looseness on water pump sprocket becomes maxi-
mum. 

b.

Screw M8 bolts (A) [pitch: 1.25 mm (0.049 in) length: approx. 50
mm (1.97 in)] into water pumps upper and lower mounting bolt
holes until they reach timing chain case. Then, alternately
tighten each bolt for a half turn, and pull out water pump (1).

CAUTION:

• Pull straight out while preventing vane from contacting

socket in installation area.

• Remove water pump without causing sprocket to contact

timing chain.

c.

Remove M8 bolts and O-rings from water pump.

CAUTION:

Never disassemble water pump.

INSTALLATION

1.

Install new O-rings to water pump.
• Apply engine oil to O-ring (1) and engine coolant to O-ring (3)

as shown in the figure.

• Locate O-ring with yellow paint mark (A) to front side.
• Locate O-ring with light blue paint mark (B) to rear side.

2.

 Install water pump.

CAUTION:

Never allow cylinder block to nip O-rings when installing water pump.
• Check timing chain and water pump sprocket are engaged.
• Insert water pump by tightening mounting bolts alternately and evenly.

3.

Install timing chain tensioner (primary) as follows:

a.

Turn crankshaft clockwise so that timing chain on the timing chain tensioner (primary) side is loose.

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WATER PUMP

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b.

Pull plunger stopper tab (A) up (or turn lever downward) so as to
remove plunger stopper tab from the ratchet of plunger (D).
NOTE:
Plunger stopper tab and lever (C) are synchronized.

c.

Push plunger into the inside of tensioner body.

d.

Hold plunger in the fully compressed position by engaging
plunger stopper tab with the tip of ratchet.

e.

To secure lever, insert stopper pin (E) through hole of lever into
tensioner body hole (B).
• The lever parts and the tab are synchronized. Therefore, the

plunger will be secured under this condition.

NOTE:
Figure shows the example of 1.2 mm (0.047 in) diameter thin screwdriver being used as the stopper pin.

f.

Install timing chain tensioner (primary).
• Remove dust and foreign material completely from backside of timing chain tensioner (primary) and

from installation area of rear timing chain case.

g.

Remove stopper pin.

h.

Check again that timing chain and water pump sprocket are engaged.

4.

Install in the reverse order of removal for remaining parts.
• After starting engine, let idle for three minutes, then rev engine up to 3,000 rpm under no load to

purge air from the high-pressure chamber of chain tensioner. Engine may produce a rattling
noise. This indicates that air still remains in the chamber and is not a matter of concern.

Inspection

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INSPECTION AFTER REMOVAL

• Check for badly rusted or corroded water pump body assembly.
• Check for rough operation due to excessive end play.
• If anything is found, replace water pump.

INSPECTION AFTER INSTALLATION

• Check that the reservoir tank cap is tightened.
• Check for leaks of engine coolant using the radiator cap tester adapter [SST: EG17650301 (J33984-A)] and

the radiator cap tester (commercial service tool). Refer to 

CO-8, "Inspection"

.

• Start and warm up the engine. Visually check that there is no leaks of engine coolant.

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