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Infiniti I35 (A33). Manual - part 496

AEM023

Inspection

NHEM0054

PISTON AND PISTON PIN CLEARANCE

NHEM0054S01

Measure inner diameter of piston pin hole “dp”.

Standard diameter “dp”:

Grade No. 0

21.993 - 21.999 mm (0.8659 - 0.8661 in)

Grade No. 1

21.999 - 22.005 mm (0.8661 - 0.8663 in)

AEM024

Measure outer diameter of piston pin “Dp”.

Standard diameter “Dp”:

Grade No. 0

21.989 - 21.995 mm (0.8657 - 0.8659 in)

Grade No. 1

21.995 - 22.001 mm (0.8659 - 0.8662 in)

Calculate interference fit of piston pin to piston.

Dp − dp = 0.002 - 0.006 mm (0.0001 - 0.0002 in)

If it exceeds the above value, replace piston assembly with pin.

SEM024AA

PISTON RING SIDE CLEARANCE

NHEM0054S02

Side clearance:

Top ring

0.045 - 0.080 mm (0.0018 - 0.0031 in)

2nd ring

0.030 - 0.070 mm (0.0012 - 0.0028 in)

Oil ring

0.065 - 0.135 mm (0.0026 - 0.0053 in)

Max. limit of side clearance:

Top ring 0.11 mm (0.0043 in)
2nd ring 0.1 mm (0.004 in)

If out of specification, replace piston ring. If clearance exceeds
maximum limit with new ring, replace piston.

SEM599A

PISTON RING END GAP

NHEM0054S03

End gap:

Top ring 0.23 - 0.33 mm (0.0091 - 0.0130 in)
2nd ring 0.33 - 0.48 mm (0.0130- 0.0189 in)
Oil ring 0.20 - 0.60 mm (0.0079 - 0.0236 in)

Max. limit of ring gap:

Top ring 0.54 mm (0.0213 in)
2nd ring 0.80 mm (0.0315 in)
Oil ring 0.95 mm (0.0374 in)

IDX

CYLINDER BLOCK

Inspection

EM-75

If out of specification, replace piston ring. If gap still exceeds the
limit even with a new ring, do the following. Rebore cylinder and
use oversized piston and piston rings.
Refer to SDS (EM-94).

When replacing the piston, check the cylinder block surface for
scratches or seizure. If scratches or seizure is found, hone or
replace the cylinder block.

SEM038F

SEM003F

CONNECTING ROD BEND AND TORSION

NHEM0054S04

Bend:

Limit 0.15 mm (0.0059 in)
per 100 mm (3.94 in) length

Torsion:

Limit 0.30 mm (0.0118 in)
per 100 mm (3.94 in) length

If it exceeds the limit, replace connecting rod assembly.

SEM123C

CYLINDER BLOCK DISTORTION AND WEAR

NHEM0054S05

Clean upper surface of cylinder block.
Use a reliable straightedge and feeler gauge to check the flat-
ness of cylinder block surface.
Check along six positions shown in the figure.

Distortion limit: 0.10 mm (0.0039 in)

If out of specification, resurface it. The limit for cylinder block
resurfacing is determined by cylinder head resurfacing in
engine.
Resurfacing limit:
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)

Nominal cylinder block height from crankshaft center:

214.95 - 215.05 mm (8.4626 - 8.4665 in)
Refer to SDS (EM-93).

If necessary, replace cylinder block.

CYLINDER BLOCK

Inspection (Cont’d)

EM-76

SEM843E

SEM321AA

PISTON-TO-BORE CLEARANCE

NHEM0054S06

Using a bore gauge, measure cylinder bore for wear, out-of-
round and taper.

Cylinder bore inner diameter

Grade No.

Standard inner diameter

Wear limit

No. 1

95.500 - 95.510 mm (3.7598 - 3.7602 in)

0.20 mm (0.0079 in)

No. 2

95.510 - 95.520 mm (3.7602 - 3.7606 in)

No. 3

95.520 - 95.530 mm (3.7606 - 3.7610 in)

If it exceeds the limit, rebore all cylinders. Replace cylinder
block if necessary.

Out-of-round (Difference between X and Y):

Limit 0.015 mm (0.0006 in)

Taper (Difference between A and C):

Limit 0.015 mm (0.0006 in)

Check for scratches and seizure. If seizure is found, hone it.

SEM756G

If both cylinder block and piston are replaced with new
ones, select piston of the same grade number punched on
cylinder block rear position. These numbers are punched
in either Arabic or Roman numerals.

SEM258C

Measure piston skirt diameter.

Piston diameter “A”: Refer to SDS (EM-94).
Measuring point “a” (Distance from the top):

41.0 mm (1.61 in)

Check that piston-to-bore clearance is within specification.

Piston-to-bore clearance “B”:

0.010 - 0.030 mm (0.0004 - 0.0012 in)

Determine piston oversize according to amount of cylinder
wear.
Oversize pistons are available for service.
Refer to SDS (EM-94).

If oversize piston is used, use it for all cylinders with over-
size piston rings.

Cylinder bore size is determined by adding piston-to-bore
clearance to piston diameter “A”.

Rebored size calculation: D = A + B − C

where,
D: Bored diameter
A: Piston diameter as measured
B: Piston-to-bore clearance
C: Honing allowance 0.02 mm (0.0008 in)

IDX

CYLINDER BLOCK

Inspection (Cont’d)

EM-77

Install main bearing caps, and tighten to the specified torque.
Otherwise, cylinder bores may be distorted in final assembly.

Cut cylinder bores.

When any cylinder needs boring, all other cylinders must
also be bored.

Do not cut too much out of cylinder bore at a time. Cut
only 0.05 mm (0.0020 in) or so in diameter at a time.

Hone cylinders to obtain specified piston-to-bore clearance.

10. Measure finished cylinder bore for out-of-round and taper.

Measurement should be done after cylinder bore cools
down.

SEM316A

CRANKSHAFT

NHEM0054S07

Check crankshaft main and pin journals for score, wear or
cracks.

With a micrometer, measure journals for taper and out-of-
round.

Out-of-round (X − Y):

Standard

0.002 mm (0.0001 in)

Taper (A − B):

Standard

0.002 mm (0.0001 in)

SEM346D

Measure crankshaft runout.

Place a V-block on a precise flat table to support the journals
on the both end of the crankshaft.

Place a dial gauge straight up on the No. 3 journal.

While rotating the crankshaft, read the movement of the
pointer on the dial gauge. (Total indicator reading)

Runout (Total indicator reading):

Limit 0.10 mm (0.0039 in)

If it exceeds the limit, replace crankshaft.

SEM175F

BEARING CLEARANCE

NHEM0054S08

Use either of the following two methods, however, method “A”
gives more reliable results and is preferable.

Method A (Using bore gauge & micrometer)

Main bearing

NHEM0054S0801

Set main bearings in their proper positions on cylinder block
and main bearing cap.

CYLINDER BLOCK

Inspection (Cont’d)

EM-78

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