Nissan Altima L32. Manual - part 637

EM-84

< DISASSEMBLY AND ASSEMBLY >

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CYLINDER BLOCK

• Using a dial gauge, measure the clearance between the thrust

bearings and the crankshaft arm when the crankshaft is moved

fully forward or backward.

• If the measured value exceeds the limit, replace the thrust bear-

ings, and measure again. If it still exceeds the limit, replace the

crankshaft.

CONNECTING ROD SIDE CLEARANCE

• Measure side clearance between connecting rod and crankshaft

arm using a feeler gauge.

• If the measured value exceeds the limit, replace the connecting

rod bearings, and measure again. If it still exceeds the limit,

replace the crankshaft also.

PISTON AND PISTON PIN CLEARANCE

Diameter of Piston Pin Bore

• Measure the diameter of piston pin bore using an inside microme-

ter. Refer to 

EM-99, "Standard and Limit"

.

Outer Diameter of Piston Pin

• Measure outer diameter of piston pin using a micrometer. Refer to

EM-99, "Standard and Limit"

.

Piston to Piston Pin Clearance

Standard

: 0.10 - 0.26 mm (0.0039 - 0.0102 in)

Limit

: 0.30 mm (0.0118 in)

PBIC0268E

Standard

: 0.20 - 0.35 mm (0.0079 - 0.0138 in)

Limit

: 0.50 mm (0.0197 in)

KBIA0071E

PBIC0116E

PBIC0117E

CYLINDER BLOCK

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(Piston pin clearance) = (Piston pin bore diameter) – (Outer diameter

of piston pin)

• A: Front mark

• B: Piston pin bore grade

• C: Piston grade I.D. stamp

• D: Piston crown I.D. code stamp

• If clearance exceeds specification, replace either or both of piston/

piston pin assembly and connecting rod assembly with reference

to specification of each parts.

• Use the piston selection table to replace piston/piston pin assem-

bly. Refer to 

EM-93, "How to Select Piston and Bearing"

.

• Use the connecting rod bearing selection table to replace connecting rod. Refer to 

EM-93, "How to Select

Piston and Bearing"

.

NOTE:

• The connecting rod small end grade and piston pin hole (piston

pin) grade are provided only for the parts installed at the plant. For

service parts, no grades can be selected. Only 0 grade is avail-

able. 

• Follow the "CONNECTING ROD BUSHING OIL CLEARANCE

(SMALL END)" procedure for the values for each grade at the

plant.

PISTON RING SIDE CLEARANCE

• Measure side clearance of piston ring and piston ring groove using

a feeler gauge. Refer to 

EM-99, "Standard and Limit"

.

• If out of specification, replace piston and/or piston ring assembly.

PISTON RING END GAP

• Check if inner diameter of cylinder bore is within specification.

Follow the "PISTON TO CYLINDER BORE CLEARANCE" proce-

dure.

• Insert piston ring until middle of cylinder with piston, and measure

gap using a feeler gauge. Refer to 

EM-99, "Standard and Limit"

.

• If out of specification, replace piston ring.

CONNECTING ROD BEND AND TORSION

Standard

: 0.002 - 0.006 mm (0.0001 - 0.0002 in)

ALBIA0209ZZ

SBIA0282E

SEM024AA

SEM822B

EM-86

< DISASSEMBLY AND ASSEMBLY >

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CYLINDER BLOCK

• Check with connecting rod aligner. Refer to 

EM-99, "Standard and

Limit"

.

• If it exceeds the limit, replace connecting rod assembly.

CONNECTING ROD BEARING (BIG END)

• Install the connecting rod cap without the connecting rod bearing

installed. After tightening the connecting rod bolt to the specified

torque, measure the connecting rod big end inner diameter using

an inside micrometer. Refer to 

EM-99, "Standard and Limit"

.

CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)

Inner Diameter of Connecting Rod (Small End)

• Measure inner diameter of bushing. Refer to 

EM-99, "Standard and

Limit"

Outer Diameter of Piston Pin

SEM003F

SEM038F

PBIC0119E

PBIC0120E

CYLINDER BLOCK

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• Measure outer diameter of piston pin. Refer to 

EM-99, "Standard

and Limit"

.

Piston Pin to Connecting Rod Bushing Clearance (Small End)

(Piston pin to connecting rod bushing clearance (small end)) = (Inner

diameter of connecting rod small end) – (Outer diameter of piston

pin)

• If the measured value exceeds the standard, replace the connect-

ing rod assembly and/or piston and piston pin assembly.

• If replacing the piston and piston pin assembly, use the "Piston

Selection Table" to select the piston corresponding to the applica-

ble bore grade of the cylinder block to be used. Refer to 

EM-93,

"How to Select Piston and Bearing"

.

Factory Installed Parts Grading:

• Service parts apply only to grade 0 (B).

Unit: mm (in)

• A: Front mark

• C: Piston grade I.D. stamp

• D: Piston crown I.D. code stamp

CYLINDER BLOCK DISTORTION

• Using a scraper, remove gasket on the cylinder block surface, and also remove oil, scale, carbon, or other

contamination. 

CAUTION:

Be careful not to allow gasket debris to enter the oil or coolant passages.

• Measure the distortion on the block upper face at some different

points in 6 directions.

• If out of the distortion limit, replace the cylinder block and lower

block they are machined together as an assembly.

INNER DIAMETER OF MAIN BEARING HOUSING

PBIC0117E

Standard

: 0.005 - 0.017 mm (0.0002 - 0.0007 in)

SBIA0282E

Piston Pin Grade (B)

                    0

                    1

Connecting rod small end 
inner bushing diameter

         20.000 - 20.006          
       (0.7874 - 0.7876)

         20.006 - 20.012
        (0.7876 - 0.7879)

Piston pin outer diameter

        19.989 - 19.995
       (0.7870 - 0.7872)

         19.995 - 20. 001
        (0.7872 - 0.7874)

Piston pin bore diameter

        19.993 - 19.999
       (0.7871- 0.7874)

         19.999 - 20.005
        (0.7874 - 0.7876)

ALBIA0209ZZ

Limit

: 0.1 mm (0.004 in)

PBIC0121E