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Nissan Frontier. Manual - part 728

HOW TO SELECT PISTON AND BEARING

EM-101

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HOW TO SELECT PISTON AND BEARING

How to Select Piston and Bearing

INFOID:0000000009478081

DESCRIPTION

*For the service parts, the grade for fitting cannot be selected between piston pin and connecting rod. (Only grade “0” 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, follow the applicable procedures.

HOW TO SELECT PISTON

When New Cylinder Block Is Used

• Check the cylinder bore grade on rear-left side of cylinder block,

and select piston of the same grade.

• If there is a corrected stamp mark on cylinder block, use it as a cor-

rect reference.

When Cylinder Block Is Reused

Selection points

Selection parts

Selection items

Selection methods

Between cylinder block and
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 journal
grade (outer diameter of jour-
nal)

Between crankshaft and con-
necting rod

Connecting rod bearing

Connecting rod bearing grade
(bearing thickness)

Combining service grades for
connecting rod big end diame-
ter and crankshaft pin outer di-
ameter determine connecting
rod bearing selection.

Between cylinder block and pis-
ton

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

Piston grade (piston skirt diam-
eter)

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

Between piston and connecting
rod

—

SBIA0283E

PBIC3019E

EM-102

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HOW TO SELECT PISTON AND BEARING

1. Measure the cylinder bore inner diameter. Refer to

EM-91, "Inspection After Disassembly"

2. Determine the bore grade by comparing the measurement with the values under the cylinder bore inner

diameter of the “Piston Selection Table”.

3. Select piston of the same grade.

Piston Selection Table

Unit: mm (in)

NOTE:

• There is no piston grade “1”.

• Piston is available together with piston pin as an assembly.

• The piston pin (piston pin hole) grade is provided only for the parts installed at the plant. For service parts, no

grades can be selected. (Only grade “0” is available.)

HOW TO SELECT CONNECTING ROD BEARING

When New Connecting Rod and Crankshaft Are Used

1. Apply connecting rod big end diameter grade stamped on con-

necting rod side face to the row in the “Connecting Rod Bearing

Selection Table”.

2. Apply crankshaft pin journal diameter grade stamped on crank-

shaft front side to the column in the “Connecting Rod Bearing

Selection Table”.

3. Read the symbol at the cross point of selected row and column in the “Connecting Rod Bearing Selection

Table”.

4. Apply the symbol obtained to the “Connecting Rod Bearing Grade Table” to select connecting rod bearing.

When Crankshaft and Connecting Rod Are Reused

1. Measure the dimensions of the connecting rod big end diameter and crankshaft pin journal diameter indi-

vidually. Refer to

EM-91, "Inspection After Disassembly"

and

EM-91, "Inspection After Disassembly"

2. Apply the measured dimension to the “Connecting Rod Bearing Selection Table”.
3. Read the symbol at the cross point of selected row and column in the “Connecting Rod Bearing Selection

Table”.

4. Apply the symbol obtained to the “Connecting Rod Bearing Grade Table” to select connecting rod bearing.

Grade number (Mark)

2 (or no mark)

Cylinder bore Inner diameter

89.010 - 89.020 (3.5043 - 3.5047)

89.020 - 89.030 (3.5047 - 3.5051)

Piston skirt diameter

88.990 - 89.000 (3.5035 - 3.5039)

89.000 - 89.010 (3.5039 - 3.5043)

PBIC2196E

PBIC2198E

HOW TO SELECT PISTON AND BEARING

EM-103

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Connecting Rod Bearing Selection Table

Connecting Rod Bearing Grade Table

Unit: mm (in)

*: Always check with the Parts Department for the latest parts information.

Undersize 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 (US) bearing, measure the connecting rod bearing inner diameter with bearing

installed, and grind the crankshaft pin so that the connecting rod bearing oil clearance satisfies the standard.

CAUTION:

WBIA0838E

Grade number*

Thickness

1.493 - 1.496

(0.0588 - 0.0589)

1.496 - 1.499

(0.0589 - 0.0590)

1.499 - 1.502

(0.0590 - 0.0591)

1.502 - 1.505

(0.0591 - 0.0593)

1.505 - 1.508

(0.0593 - 0.0594)

Identification col-
or

Black

Brown

Green

Yellow

Blue

EM-104

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HOW TO SELECT PISTON AND BEARING

In grinding crankshaft pin to use undersize bearings, keep the

fillet R [1.5 - 1.7 mm (0.059 - 0.067 in)].

Bearing undersize table

Unit: mm (in)

HOW TO SELECT MAIN BEARING

When New Cylinder Block and Crankshaft Are Used

1. “Main Bearing Selection Table” rows correspond to main bearing

housing grade on rear-left side of cylinder block.

• If there is a corrected stamp mark on cylinder block, use it as a

correct reference.

2. Apply main journal diameter grade stamped on crankshaft front

side to column in the “Main Bearing Selection Table”.

3. Read the symbol at the cross point of selected row and column in the “Main Bearing Selection Table”.

CAUTION:

There are two main bearing selection tables. One is for odd-numbered journals (No. 1, 3 and 5) and

the other is for even-numbered journals (No. 2 and 4). Make certain to use the appropriate table.

This is due to differences in the specified clearances.

4. Apply the symbol obtained to the “Main Bearing Grade Table” to select main bearing.

NOTE:

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

When Cylinder Block and Crankshaft Are Reused

1. Measure the dimensions of the cylinder block main bearing housing inner diameter and crankshaft main

journal diameter individually. Refer to

EM-91, "Inspection After Disassembly"

and

EM-91, "Inspection After

Disassembly"

2. Apply the measured dimension to the “Main Bearing Selection Table”.
3. Read the symbol at the cross point of selected row and column in the “Main Bearing Selection Table”.

PBIC2200E

Size

Thickness

US 0.25 (0.0098)

1.624 - 1.632 (0.0639 - 0.0642)

SBIA0283E

PBIC2198E

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