Nissan Frontier. Manual - part 708

CAMSHAFT VALVE CLEARANCE

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• Measure the valve clearances at locations marked “

×” as

shown in the table below (locations indicated with black arrow

shown) with feeler gauge.

• No. 1 cylinder compression TDC

c. Rotate crankshaft one revolution (360

°) and align TDC mark to

timing indicator on front cover. 

• Measure the valve clearance at locations marked “

×” as shown

in the table below (locations indicated with black arrow shown)

with feeler gauge. 

• No. 4 cylinder compression TDC

5. If out of standard, perform adjustment. 

ADJUSTMENT

• Perform adjustment depending on selected head thickness of valve lifter.
1. Measure the valve clearance.
2. Remove camshaft. Refer to 

EM-54, "Removal and Installation"

.

3. Remove valve lifters at the locations that are out of the standard.
4. Measure the center thickness of the removed valve lifters with a

micrometer.

5. Use the equation below to calculate valve lifter thickness for replacement.

Measuring position

No. 1 CYL.

No. 2 CYL.

No. 3 CYL.

No. 4 CYL.

No. 1 cylinder at 
compression TDC

INT

×

×

EXH

×

×

PBIC3017E

PBIC3015E

Measuring position

No. 1 CYL.

No. 2 CYL.

No. 3 CYL.

No. 4 CYL.

No. 4 cylinder at 
compression TDC

INT

×

×

EXH

×

×

PBIC3026E

KBIA0057E

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CAMSHAFT VALVE CLEARANCE

• Thickness of new valve lifter can be identified by stamp marks

on the reverse side (inside the cylinder).

Stamp mark “696” indicates 6.96 mm (0.2740 in) in thickness.

NOTE:

Available thickness of valve lifter: 26 sizes range 6.96 to 7.46 mm (0.2740 to 0.2937 in) in steps of 0.02

mm (0.0008 in) (when manufactured at factory). Refer to 

EM-108, "Standard and Limit"

.

6. Install the selected valve lifter.
7. Install camshaft. Refer to 

EM-54, "Removal and Installation"

.

8. Manually rotate crankshaft pulley a few rotations. 
9. Make sure that the valve clearances for cold engine are within specifications by referring to the specified

values. 

10. Installation of the remaining components is in the reverse order of removal.
11. Start the engine, and check for unusual noise and vibration.

Valve lifter thickness calculation:

t = t

1

 + (C

1

– C

2

)

t

= Valve lifter thickness to be replaced

t

1

= Removed valve lifter thickness

C

1

= Measured valve clearance

C

2

= Standard valve clearance:

Intake

: 0.28 mm (0.011 in)

Exhaust

: 0.30 mm (0.012 in)

KBIA0119E

COMPRESSION PRESSURE

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COMPRESSION PRESSURE

Compression Pressure

INFOID:0000000009478048

CHECKING COMPRESSION PRESSURE

1. Warm up engine thoroughly. 
2. Release fuel pressure. Refer to 

EC-466, "Fuel Pressure Check"

.

3. Disconnect fuel pump fuse to avoid fuel injection during mea-

surement.

4. Remove spark plug from each cylinder. Refer to 

EM-18, "Removal and Installation"

.

5. Connect engine tachometer (not required in use of CONSULT.
6. Install compression tester with an adapter into spark plug hole.

• Use the adapter whose pick up end inserted to spark plug hole

is smaller than 20 mm (0.79 in) in diameter. Otherwise, it may

be caught by cylinder head during removal.

7. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge

pointer stabilizes, read the compression pressure and the engine rpm. Perform these steps to check each

cylinder.

Compression pressure:

Unit: kPa (kg/cm

2

, psi) /rpm

CAUTION:

Always use fully a charged battery to obtain the specified engine speed.

• If the engine speed is out of the specified range check the battery and recharge as necessary. Check

the engine speed again with the battery properly charged. 

BBIA0534E

LBIA0448E

SBIA0533E

Standard

Minimum

Differential limit between cylinders

 1,304 (13.3, 189) / 250

 1,108 (11.3, 161) / 250

      100 (1.0, 14) / 250

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COMPRESSION PRESSURE

• If some cylinders have low compression pressure, pour a small amount of engine oil into the spark plug

hole of the cylinder to re-check it for compression.

- If the added engine oil improves the compression, piston rings may be worn out or damaged. Check the

piston rings and replace if necessary

- If the compression pressure remains at a low level despite the addition of engine oil, the valves may be

malfunctioning. Check the valves for damage. Replace the valve or valve seat accordingly.   

- If two adjacent cylinders have low compression pressure and their compression remains low even after

the addition of engine oil, cylinder head gaskets may be leaking. 

• If the compression pressure is below the minimum value, check the valve clearances and parts associ-

ated with the combustion chamber (valve, valve seat, piston, piston ring, cylinder bore, cylinder head,

cylinder head gasket). After repairing as necessary, measure the compression pressure again.

8. After inspection is completed, install removed parts.
9. Start engine, and make sure that engine runs smoothly. 
10. Perform trouble diagnosis. If DTC appears, erase it. Refer to 

EC-138, "Inspection Procedure"

.