Nissan Pathfinder. Instruction - part 572

CYLINDER BLOCK

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

after boring.

7. 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.

8. Hone cylinders to obtain specified piston-to-bore clearance.
9. Measure finished cylinder bore for out-of-round and taper.

• Measurement should be done after cylinder bore cools down.

CRANKSHAFT

1. Check the crankshaft main and pin journals for scoring, wear, or

cracks.

2. Measure the journals for taper and out-of-round.

3. Measure crankshaft runout.
a. Place a V-block on a precise flat table to support the journals on

the both ends of the crankshaft.

b. Place a dial gauge straight up on the No. 3 journal. 
c. While rotating the crankshaft, read the movement of the pointer

on the dial gauge. 

BEARING CLEARANCE

• Use either of the following two methods, however method (A) gives more reliable results and so is the pre-

ferred method.

Method A (Using Bore Gauge and Micrometer)

Main Bearing
1. Set the main bearings in their proper positions on the cylinder

block and the main bearing cap.

2. Install the main bearing caps and bearing beam to the cylinder

block. Tighten all bolts in the numerical order as specified. Refer

to 

EM-112, "Disassembly and Assembly"

.

Standard
Out-of-round (X - Y) : 0.002 mm (0.0001 in)
Taper (A - B)

: 0.002 mm (0.0001 in)

SEM316A

Runout limit (total indicator 
reading)

: 0.10 mm (0.0039 in)

SEM346D

SEM175F

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CYLINDER BLOCK

3. Measure the inner diameters (A) of each main bearing as

shown.

4. Measure the outer diameters (Dm) of each crankshaft main jour-

nal as shown.

5. Calculate the main bearing clearance.

Main bearing clearance = (A)- (Dm)

• If it exceeds the limit, replace the bearing.

• If clearance cannot be adjusted using any standard bearing

grade, grind crankshaft journal and use an undersized bear-

ing.

• When grinding the crankshaft journal, confirm that the (L)

dimension in the fillet role is more than the specified limit.

6. If the crankshaft or the cylinder block is replaced with a new one, select thickness of the main bearings as

follows:

a. The grade number of each cylinder block main journal is

punched on the respective cylinder block. These numbers are

punched in either Arabic or Roman numerals. If measured diam-

eter is out of the grade punched, decide suitable grade from

available main bearings.

SEM845E

Standard

: 0.035 - 0.045 mm (0.0014 - 0.0018 in)

Limit

: 0.065 mm (0.0026 in)

AEM033

(L) 

: 0.10 mm (0.0039 in)

SEM964

SEM756G

CYLINDER BLOCK

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b. The grade number of each crankshaft main journal is punched

on the crankshaft end. These numbers are punched in either

Arabic or Roman numerals. If measured diameter is out of grade

punched, decide the suitable grade from available main bear-

ings.

c. Select the main bearing suitable thickness according to the following table:

Connecting Rod Bearing (Big End)

1. Install the connecting rod bearing to the connecting rod and cap.
2. Install the connecting rod cap to the connecting rod. Tighten to specification. Refer to 

EM-112, "Disassem-

bly and Assembly"

.

SEM452G

PBIC0814E

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CYLINDER BLOCK

3. Measure the inner diameter (C) of each connecting rod (big end)

as shown.

4. Measure the outer diameter (Dp) of each crankshaft pin journal.
5. Calculate the connecting rod bearing clearance.

Connecting rod bearing clearance = (C) - (Dp)

6. If the calculated clearance exceeds the specified limit, replace

the bearings.

7. If the clearance cannot be adjusted within the standard of any

bearing, grind the crankshaft journal and use undersized bear-

ings.

8. If the crankshaft is replaced with a new one, select the connect-

ing rod bearings according to the following table:

Connecting Rod Bearing Grade Number (Identification

Color)

These numbers are punched in either Arabic or Roman numer-

als.

Method B (Using Plastigage)

• Remove engine oil and dust on the crankshaft pin and the surfaces

of each bearing completely. 

• Cut a Plastigage slightly shorter than the bearing width, and place

it in crankshaft axial direction, avoiding oil holes.

• Install the connecting rod bearings to the connecting rod cap, and

tighten the connecting rod nuts to the specified torque. 

CAUTION:

Do not rotate the crankshaft.

• Remove the connecting rod cap and bearings, and using the scale

on the Plastigage bag, measure the Plastigage width. 

NOTE:

The procedure when the measured value exceeds the repair limit

is same as that described in "Method A (Using Bore Gauge and Micrometer)".

DRIVE PLATE RUNOUT 

AEM027

Standard

: 0.020 - 0.045 mm (0.0008 - 0.0018 in)

Limit

: 0.070 mm (0.0028 in)

AEM034

Crankshaft pin journal grade 

number

Connecting rod bearing grade 

number

                          0

                    0 (black)

                          1

                    1 (brown)

                          2

                    2 (green)

SEM452G

SEM142