Nissan Silvia. Instruction — part 232

SEM993E

20. Remove camshafts and camshaft brackets, oil tubes and baffle

plate.

SEM994E

21. Remove exhaust manifold with turbocharger. Refer to EM-58,

“Removal”.

SEM995E

22. Remove cylinder head outside bolts and inside sub-bolts.

SEM996E

23. Remove cylinder head bolts.

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Bolts should be loosened in two or three steps.

24. Remove cylinder head completely with intake manifold.

Disassembly

NMEM0018

CAUTION:

GI

MA

LC

EC

FE

CL

MT

AT

PD

AX

SU

BR

ST

RS

BT

HA

SC

EL

IDX

CYLINDER HEAD

Removal (Cont’d)

EM-41

AEM116

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If a hydraulic lash adjuster is kept on its side, there is a
risk of air entering it. When hydraulic lash adjusters are
removed, stand them straight up or soak them in new
engine oil.

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Do not disassemble hydraulic lash adjusters.

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Attach tags to lash adjusters so as not to mix them up.

SEM057G

1.

Remove rocker arms, shims, rocker arm guides and hydraulic
lash adjusters from cylinder head.

CAUTION:

Keep parts in order so they can be installed in their original
positions during assembly.
2.

Remove intake manifold.
Refer to EM-39, “Removal”.

SEM082D

3.

Remove water outlet.

4.

Remove intake manifold with intake manifold collector.
Refer to EM-39, “Removal”.

SEM604E

5.

Remove valve components with Tool. Install camshaft tempo-
rarily.

SEM054G

6.

Remove valve oil seal with a suitable tool.

CYLINDER HEAD

Disassembly (Cont’d)

EM-42

SEM925C

Inspection

NMEM0019

CYLINDER HEAD DISTORTION

NMEM0019S01

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Clean mating surface of cylinder head.

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Use a reliable straightedge and feeler gauge to check the flat-
ness of cylinder head mating surface.

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Check along six positions shown in figure.

Head surface flatness:

Standard: Less than 0.03 mm (0.0012 in)
Limit: 0.1 mm (0.004 in)

If beyond the specified limit, replace or resurface it.
Resurfacing limit:
The limit for cylinder head resurfacing is determined by the
amount of cylinder block resurfacing.
Amount of cylinder head resurfacing is “A”.
Amount of cylinder block resurfacing is “B”.

The maximum limit is as follows:

A + B = 0.2 mm (0.008 in)

After resurfacing cylinder head, check that camshaft rotates freely
by hand. If resistance is felt, cylinder head must be replaced.

Nominal cylinder head height:

136.9 - 137.1 mm (5.390 - 5.398 in)

SEM926C

CAMSHAFT VISUAL CHECK

NMEM0019S02

Check camshaft for scratches, seizure and wear.

CAMSHAFT RUNOUT

NMEM0019S03

1.

Measure camshaft runout at the center journal.

Runout (Total indicator reading):

Standard

Less than 0.02 mm (0.0008 in)

Limit

0.1 mm (0.004 in)

2.

If it exceeds the limit, replace camshaft.

SEM549A

CAMSHAFT CAM HEIGHT

NMEM0019S04

1.

Measure camshaft cam height.

Standard cam height:

Intake

37.920 - 38.110 mm (1.4929 - 1.5004 in)

Exhaust

37.920 - 38.110 mm (1.4929 - 1.5004 in)

Cam height wear limit:

Intake & Exhaust

0.2 mm (0.008 in)

2.

If wear is beyond the limit, replace camshaft.

GI

MA

LC

EC

FE

CL

MT

AT

PD

AX

SU

BR

ST

RS

BT

HA

SC

EL

IDX

CYLINDER HEAD

Inspection

EM-43

SEM927C

CAMSHAFT JOURNAL CLEARANCE

NMEM0019S05

1.

Install camshaft bracket and tighten bolts. Refer to EM-52.

2.

Measure inner diameter of camshaft bearing.

Standard inner diameter:

Except for No. 1 intake journal

28.000 - 28.021 mm (1.1024 - 1.1032 in)

For No. 1 intake journal

28.010 - 28.031 mm (1.1028 - 1.1036 in)

SEM012A

3.

Measure outer diameter of camshaft journal.

Standard outer diameter:

27.935 - 27.955 mm (1.0998 - 1.1006 in)

4.

Calculate camshaft journal clearance.

Camshaft journal clearance = standard inner diameter
− standard outer diameter:

Standard

0.030 - 0.071 mm (0.0012 - 0.0028 in) except for No.
1 intake journal
0.040 - 0.081 mm (0.0016 - 0.0032 in) for No. 1
intake journal

Limit

0.15 mm (0.0059 in)

5.

If clearance exceeds the limit, replace camshaft and remea-
sure camshaft journal clearance.

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If clearance still exceeds the limit after replacing camshaft,
replace cylinder head.

SEM062G

CAMSHAFT END PLAY

NMEM0019S06

1.

Install camshaft in cylinder head. Refer to EM-52.

2.

Measure camshaft end play.

Camshaft end play:

Standard

0.092 - 0.173 mm (0.0036 - 0.0068 in)

Limit

0.20 mm (0.0079 in)

3.

If end play exceeds the limit, replace camshaft and remeasure
camshaft end play.

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If end play still exceeds the limit after replacing camshaft,
replace cylinder head.

CYLINDER HEAD

Inspection (Cont’d)

EM-44