Nissan Frontier. Manual - part 727

ENGINE UNIT

EM-97

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• Measure the outer diameter of crankshaft pin journal with a micrometer.

• If out of the standard, measure the connecting rod bearing oil clearance. Then use undersize bearing. Refer

to 

EM-108, "Standard and Limit"

.

OUT-OF-ROUND AND TAPER OF CRANKSHAFT

• Measure the dimensions at four different points as shown on each

main journal and pin journal with a micrometer. 

• Out-of-round is indicated by the difference in dimensions between

(X) and (Y) at (A) and (B).

• Taper is indicated by the difference in dimension between (A) and

(B) at (X) and (Y).

• If the measured value exceeds the limit, correct or replace crankshaft.

• If corrected, measure the bearing oil clearance of the corrected main journal and/or pin journal. Then select

main bearing and/or connecting rod bearing. Refer to 

EM-108, "Standard and Limit"

.

CRANKSHAFT RUNOUT 

• Place a V-block on a precise flat table to support the journals on

the both end of crankshaft.

• Place a dial indicator straight up on the No. 3 journal. 

• While rotating crankshaft, read the movement of the pointer on the

dial indicator. (Total indicator reading)

• If it exceeds the limit, replace crankshaft.

CONNECTING ROD BEARING OIL CLEARANCE

Method by Calculation

• Install connecting rod bearings to connecting rod and cap, and tighten connecting rod bolts to the specified

torque. Refer to 

EM-81, "Disassembly and Assembly"

 for tightening procedure. 

• Measure the inner diameter of connecting rod bearing with an

inside micrometer.

(Bearing oil clearance) = (Connecting rod bearing inner diameter)

– (Crankshaft pin journal diameter)

• If the clearance exceeds the limit, select proper connecting rod

bearing according to connecting rod big end diameter and crank-

shaft pin journal diameter to obtain the specified bearing oil clear-

ance. Refer to 

EM-101, "How to Select Piston and Bearing"

.

Method of Using Plastigage

• Remove engine oil and dust on 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 connecting rod bearings to connecting rod and cap, and tighten connecting rod bolts to the specified

torque. Refer to 

EM-81, "Disassembly and Assembly"

 for the tightening procedure. 

Standard: 44.956 - 44.974 mm (1.7699-1.7706 in) dia.

Limit:

Out-of-round [Difference between (X) and (Y)]

: 0.0025 mm (0.0001 in)

Taper [Difference between (A) and (B)]

: 0.0025 mm (0.0001 in)

PBIC2203E

Limit

: 0.05 mm (0.0020 in)

PBIC2541E

Standard

: 0.035 - 0.045 mm (0.0014 - 0.0018 in)

PBIC1642E

EM-98

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ENGINE UNIT

CAUTION:

Do not rotate crankshaft.

• Remove connecting rod cap and bearing, and using the scale on

the plastigage bag, measure the plastigage width. 

NOTE:

The procedure when the measured value exceeds the limit is

same as that described in the “Method by Calculation”.

MAIN BEARING OIL CLEARANCE

Method by Calculation

• Install main bearings to cylinder block and lower cylinder block, and tighten lower cylinder block bolts to the

specified torque. Refer to 

EM-81, "Disassembly and Assembly"

 for the tightening procedure. 

• Measure the inner diameter of main bearing with a bore gauge.

(Bearing oil clearance) = (Main bearing inner diameter) – (Crank-

shaft main journal diameter)

• If the clearance exceeds the limit, select proper main bearing according to main bearing inner diameter and

crankshaft main journal diameter to obtain the specified bearing oil clearance. Refer to 

EM-101, "How to

Select Piston and Bearing"

.

Method of Using Plastigage

• Remove engine oil and dust on crankshaft main journal 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 main bearings to cylinder block and lower cylinder block, and tighten lower cylinder block bolts to the

specified torque. Refer to 

EM-81, "Disassembly and Assembly"

 for the tightening procedure. 

CAUTION:

Do not rotate crankshaft.

• Remove lower cylinder block and bearings, and using the scale on

the plastigage bag, measure the plastigage width. 

NOTE:

The procedure when the measured value exceeds the limit is

same as that described in the “Method by Calculation”.

MAIN BEARING CRUSH HEIGHT 

PBIC1149E

Standard:

No. 1, 3 and 5 journals

: 0.028 - 0.042 mm (0.0011 - 0.0017 in)

No. 2 and 4 journals

: 0.041 - 0.056 mm (0.0016 - 0.0022 in)

Limit

: 0.1 mm (0.004 in)

PBIC2204E

PBIC1149E

ENGINE UNIT

EM-99

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• When lower cylinder block is removed after being tightened to the

specified torque with main bearings installed, the tip end of bearing

must protrude. Refer to 

EM-81, "Disassembly and Assembly"

 for

the tightening procedure.

• If the standard is not met, replace main bearings.

CONNECTING ROD BEARING CRUSH HEIGHT

• When connecting rod bearing cap is removed after being tightened

to the specified torque with connecting rod bearings installed, the

tip end of bearing must protrude. Refer to 

EM-81, "Disassembly

and Assembly"

   for the tightening procedure.

• If the standard is not met, replace connecting rod bearings.

LOWER CYLINDER BLOCK BOLT OUTER DIAMETER 

• Perform only with M10 bolts.

• Measure the outer diameters [(d

1)

, (d

2

)] at two positions as shown.

• If reduction appears in (A) range, regard it as (d

2)

.

• If it exceeds the limit (a large difference in dimensions), replace

lower cylinder block bolt with a new one.

CONNECTING ROD BOLT OUTER DIAMETER 

• Measure the outer diameter (d) at position as shown.

• If reduction appears in a position other than (d), regard it as (d).

• When (d) falls below the limit (when it becomes thinner), replace

connecting rod bolt with a new one.

MOVEMENT AMOUNT OF FLYWHEEL (M/T MODELS)

CAUTION:

Do not disassemble double mass flywheel.

Movement Amount of Thrust (Fore-and-Aft) Direction

• Measure the movement amount of thrust (fore-and-aft) direction when 100 N (10.2 kg, 22 lb) force is added

at the portion of 125 mm (4.92 in) radius from the center of flywheel.

Standard: There must be crush height.

SEM502G

Standard: There must be crush height.

PBIC1646E

Limit [(d

1)

– (d

2

)]: 0.13 mm (0.0051 in) 

PBIC0911E

Limit: 7.75 mm (0.3051 in)

PBIC0912E

Standard

: 1.3 mm (0.051 in) or less

EM-100

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ENGINE UNIT

• If measured value is out of the standard, replace flywheel.

Movement Amount in Radial (Rotation) Direction

Check the movement amount of radial (rotation) direction with the following procedure:
1. Install a bolt to clutch cover mounting hole, and place a torque wrench on the extended line of the flywheel

center line.

• Tighten bolt at a force of 9.8 N·m (1.0 kg-m, 87 in-lb) to keep it from loosening.

2. Put a mating mark on circumferences of the two flywheel

masses without applying any load (Measurement standard

points).

3. Apply a force of 9.8 N·m (1.0 kg-m, 87 in-lb) in each direction,

and mark the movement amount on the mass on the transmis-

sion side.

4. Measure the dimensions of movement amounts (A) and (B) on

circumference of flywheel on the transmission side.

• If measured value is out of the standard, replace flywheel.

DRIVE PLATE (A/T MODELS)

• Check drive plate and signal plate for deformation or cracks.

CAUTION:

• Do not disassemble drive plate.

• Do not place drive plate with signal plate facing down.

• When handling signal plate, take care not to damage or

scratch it. 

• Handle signal plate in a manner that prevents it from becom-

ing magnetized.

• If anything is found, replace drive plate.

Standard: 44.3 mm (1.744 in) or less.

PBIC1263E

PBIC2938E