Infiniti M45 (Y34). Manual - part 538

CYLINDER BLOCK

EM-89

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c.

Put mating (with paint) on each nut and connecting rod cap, all in the same direction (when using a pro-
tractor).

d.

Then all nuts 60 degrees clockwise (angle tightening).

CAUTION:

Always use either the angle wrench (SST) or protractor.
Avoid tightening based on visual check alone.

●

After tightening the nuts, make sure that crankshaft rotates
smoothly. 

●

Check the connecting rod side clearance. Refer to 

EM-96,

"CONNECTING ROD SIDE CLEARANCE"

16. Install knock sensor.

●

Make sure that there is no foreign material on the cylinder
block mating surface and the back surface of knock sensor. 

●

Install it with its connector facing the rear side. 

●

Do not tighten the mounting bolts while holding the connector.   

●

Make sure that knock sensor does not interfere with other-
parts.

●

Install knock sensor sub-harness with its shorter branch line
to the right bank. 

CAUTION:

If any impact by dropping is applied to knock sensor,
replace it with new one.

17. Install in the reverse order of removal.

18. Remove engine assembly from engine stand.

19. Install drive plate.

●

When installing drive plate to crankshaft,  be sure to correctly
align crankshaft side guide pin and drive plate side guide pin
hole.

–

If these are not aligned correctly, engine runs roughly and
“MIL” turns on.

●

Install drive plate, reinforcement plate and pilot converter (if
not installed in step 4) as shown in the figure.

●

Using drift of 33 mm (1.30 in) dia, push pilot converter into the
end.

●

Face pilot converter chamfered or rounded edge side to
crankshaft.

 : 14.7 N·m (1.5 kg-m, 11 ft-lb)

PBIC0104E

PBIC0105E

PBIC0106E

PBIC1965E

EM-90

CYLINDER BLOCK

How to Select Piston and Bearing 

ABS000M2

DESCRIPTION

 *For the service parts, the grade for fitting cannot be selected between a piston pin and a connecting rod.
(Only 0 grade is available.) The information at the shipment from the plant is described as a reference. 

●

The identification grade stamped on each part is the grade for the dimension measured in new condition.
This grade cannot apply to reused parts. 

●

For reused or repaired parts, measure the dimension accurately. Determine the grade by comparing the
measurement with the values of each selection table.

●

For details of the measurement method of each part, the reuse standards, and the selection method of the
selective fitting parts, refer to the text.

HOW TO SELECT PISTON
Piston Selective Fitting When New Cylinder Block is Used:

●

Check the cylinder bore grade (“1”, “2” or “3”) on the rear upper
side between cylinder block banks, and select piston of the
same grade.

NOTE:
Piston is available with piston pin as a set for the service part.
(Only “0” grade piston pin is available.)

When Cylinder Block is Reused:

1.

Measure the cylinder block bore inner diameter. Refer to 

EM-100, "Inner Diameter of Cylinder Bore"

 .

Connecting points

Connecting parts

Selection items

Selection methods

Between cylinder block to 
crankshaft

Main bearing

Main bearing grade (bearing 
thickness)

Determined by match of cylin-
der block bearing housing 
grade (inner diameter of hous-
ing) and crankshaft main jour-
nal grade (outer diameter of 
journal)

Between crankshaft to connect-
ing rod

Connecting rod bearing

Connecting rod bearing grade 
(bearing thickness)

Connecting rod bearing grade 
= crankshaft pin journal grade 
(outer diameter of pin).   No 
grade exists for inner diameter 
of connecting rod large end.

Between cylinder block to pis-
ton

Piston and piston pin assembly.
The piston is available together 
with piston pin as an assembly.

Piston grade (piston outer 
diameter)

Piston grade = cylinder bore 
grade (inner diameter of bore)

*Between piston to connecting 
rod

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PBIC2371E

PBIC2372E

CYLINDER BLOCK

EM-91

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2.

Determine the bore grade by comparing the measurement with the values under the “Cylinder bore inner
diameter” of the piston selection table. Select piston of the same grade.

Piston Selection Table

Unit: mm (in)

NOTE:

●

The piston is available together with piston pin as an assembly. 

●

The piston pin (piston pin bore) grade is provided only for the parts installed at the plant. For the service
parts, no grades can be selected (Only 0 grade is available.).

●

No second grade mark is available on piston.

HOW TO SELECT CONNECTING ROD BEARING
When New Connecting Rod and Crankshaft are Used:

●

Compare the pin diameter grade (“0”, “1” or “2”) on the crank-
shaft front surface with the values of the selection table of con-
necting rod bearing. 

NOTE:
There is no grading for connecting rod big end diameter.

When Crankshaft and Connecting Rod are Reused:

1.

Measure the connecting rod big end diameter. Refer to 

EM-98, "CONNECTING ROD BIG END DIAME-

TER"

 .

2.

Make sure that the connecting rod big end diameter is within the standard value.

3.

Measure the crankshaft pin journal diameter. Refer to 

EM-102, "CRANKSHAFT PIN JOURNAL DIAME-

TER"

 .

4.

Determine the grade of crankshaft pin journal diameter grade by corresponding to the measured dimen-
sion in “Crankshaft pin journal diameter” column of “Selection Table of Connecting Rod Bearing”.

5.

Select connecting rod bearing of the same grade.

Selection Table of Connecting Rod Bearing

Unit: mm (in)

Unit: mm (in)

Under Size Bearings Usage Guide

●

When the specified connecting rod bearing oil clearance is not obtained with standard size connecting rod
bearings, use undersize (US) bearings.

●

When using undersize bearings, measure the connecting rod bearing inner diameter with bearings
installed, and grind crankshaft pin so that the connecting rod bearing oil clearance satisfies the standard. 

   Bearing undersize table

Grade number (Mark)

1

   2 (or no mark)

3

Inner diameter of cylinder bore

93.000-93.010 (3.6614-3.6618)

93.010-93.020 (3.6618-3.6622)

93.020-93.030 (3.6622-3.6626)

Outer diameter of piston

92.980-92.990 (3.6606-3.6610)

92.990-93.000 (3.6610-3.6614)

93.000-93.010 (3.6614-3.6618)

PBIC2374E

Connecting rod big end diameter

55.000 - 55.013 (2.1654 - 2.1659)

Crankshaft pin journal diameter

Grade (Mark)

Dimension (Bearing thickness range)

Bearing grade No.

Color

51.968 - 51.974 (2.0460 - 2.0462)

0

1.500 - 1.503 (0.0591 - 0.0592)

STD 0

No color

51.962 - 51.968 (2.0457 - 2.0460)

1

1.503 - 1.506 (0.0592 - 0.0593)

STD 1

Brown

51.956 - 51.962 (2.0455 - 2.0457)

2

1.506 - 1.509 (0.0593 - 0.0594)

STD 2

Green

EM-92

CYLINDER BLOCK

Unit: mm (in)

CAUTION:

In grinding the crankshaft pin to use undersize bearings, do not
damage the fillet R [1.5 mm (0.059 in)] (All crankshaft pins).

HOW TO SELECT MAIN BEARING
When New Cylinder Block and Crankshaft are Used:

1.

Apply main bearing housing grade on upper rear side between
cylinder block banks to row in “Main Bearing Selection Table”.

2.

Apply journal diameter grade on crankshaft front to column in
“Main Bearing Selection Table”.

3.

Find sign at crossing of row and column in “Main Bearing Selection Table”.

CAUTION:

●

Initial clearance for No.1, 5 journal and No. 2, 3, 4 journal is different. Use two different selection
lists for each part. 

●

No.1, 5 journal and No. 2, 3, 4 journal have the same signs but different measures. Do not con-
fuse. 

4.

Apply sign at crossing in above step 3 to “Main Bearing Grade Table”.

NOTE:

●

Grade list applies to all journals.

●

Service parts is available as a set of both upper and lower.

When Cylinder Block and Crankshaft are Reused:

1.

Measure inner diameter of cylinder block main bearing housing and outer diameter of crankshaft main
journal. Refer to 

EM-100, "INNER DIAMETER OF MAIN BEARING HOUSING"

 , 

EM-102, "CRANK-

SHAFT MAIN JOURNAL DIAMETER"

 .

Size

Thickness

            US

0.25 (0.0098)

       1.626 - 1.634 (0.0640 - 0.0643)

PBIC2373E

PBIC2371E

PBIC2374E