Content .. 481 482 483 484 ..

Infiniti I30 (A33). Manual - part 483

SEM890EA

11. Align rear timing chain case with dowel pins, then install on

cylinder head and block.

12. Tighten rear chain case bolts.
a.

Tighten bolts in numerical order shown in the figure.

Repeat above step a.

This installation is the same procedure as that for timing chain.
Refer to “Installation”, EM-29.

SEM868E

Valve Clearance

NHEM0022

CHECKING

NHEM0022S01

Check valve clearance while engine is cold and not running.
1.

Remove intake manifold collector.

Remove rocker cover ornament.

Remove RH and LH rocker covers.

Remove all spark plugs.

Set No. 1 cylinder at TDC on its compression stroke.

Align pointer with TDC mark on crankshaft pulley.

Check that valve lifters on No. 1 cylinder are loose and valve
lifters on No. 4 are tight.
If not, turn crankshaft one revolution (360°) and align as above.

IDX

CYLINDER HEAD

Installation (Cont’d)

EM-51

SEM893E

Check only those valves shown in the figure.

Crank
position

Valve

No. 1

No. 2

No. 3

No. 4

No. 5

No. 6

INT EXH INT EXH INT EXH INT EXH INT EXH INT EXH

No. 1 TDC

SEM139D

Using a feeler gauge, measure clearance between valve lifter
and camshaft.

Record any valve clearance measurements which are out of
specification. They will be used later to determine the required
replacement adjusting shim.

Valve clearance for checking (Cold):

Intake

0.26 - 0.34 mm (0.010 - 0.013 in)

Exhaust

0.29 - 0.37 mm (0.011 - 0.015 in)

SEM894E

Turn crankshaft 240° and align as above.

Set No. 3 cylinder at TDC on its compression stroke.

Check only those valves shown in the figure.

Crank
position

Valve

No. 1

No. 2

No. 3

No. 4

No. 5

No. 6

INT EXH INT EXH INT EXH INT EXH INT EXH INT EXH

No. 3 TDC

CYLINDER HEAD

Valve Clearance (Cont’d)

EM-52

SEM958E

10. Turn crankshaft 240° and align as above.
11. Set No. 5 cylinder at TDC on its compression stroke.
12. Check only those valves shown in the figure.

Crank
position

Valve

No. 1

No. 2

No. 3

No. 4

No. 5

No. 6

INT EXH INT EXH INT EXH INT EXH INT EXH INT EXH

No. 5 TDC

13. If all valve clearances are within specification, install the fol-

lowing parts.

Intake manifold collector

RH and LH rocker covers

All spark plugs

Rocker cover ornament

SEM557EB

ADJUSTING

NHEM0022S02

Adjust valve clearance while engine is cold.
1.

Turn crankshaft, to position cam lobe on camshaft of valve that
must be adjusted upward.

Place Tool (A) around camshaft as shown in figure.
Before placing Tool (A), rotate notch toward center of cyl-
inder head (See figure.), to simplify shim removal later.

CAUTION:

Be careful not to damage cam surface with Tool (A).

SEM869E

Rotate Tool (A) (See figure.) so that valve lifter is pushed down.

SEM870E

Place Tool (B) between camshaft and the edge of the valve
lifter to retain valve lifter.

CAUTION:

Tool (B) must be placed as close to camshaft bracket as
possible.

Be careful not to damage cam surface with Tool (B).

Remove Tool (A).

IDX

CYLINDER HEAD

Valve Clearance (Cont’d)

EM-53

SEM871E

Blow air into the hole to separate adjusting shim from valve
lifter.

SEM872E

SEM145D

SEM873E

Remove adjusting shim using a small screwdriver and a mag-
netic finger.

Determine replacement adjusting shim size following formula.

Using a micrometer determine thickness of removed shim.

Calculate thickness of new adjusting shim so valve clearance
comes within specified values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance

Intake:

N = R + [M − 0.30 mm (0.0118 in)]

Exhaust:

N = R + [M − 0.33 mm (0.0130 in)]

Shims are available in 64 sizes from 2.32 mm (0.0913 in)
to 2.95 mm (0.1161 in), in steps of 0.01 mm (0.0004 in).

Select new shim with thickness as close as possible to calcu-
lated value.

SEM146D

Install new shim using a suitable tool.

Install with the surface on which the thickness is stamped
facing down.

CYLINDER HEAD

Valve Clearance (Cont’d)

EM-54

Content .. 481 482 483 484 ..