Nissan Frontier. Instruction — part 761
ENGINE UNIT
EM-233
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• Install connecting rod bearing cap without installing connecting rod
bearing, and tightening connecting rod bolts to the specified
torque. Refer to
EM-220, "Disassembly and Assembly"
for the
tightening procedure.
• Measure the inner diameter of connecting rod big end with inside
micrometer.
• If out of the standard, replace connecting rod assembly.
CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END)
Connecting Rod Bushing Inside Diameter (Small End)
Measure inside diameter of connecting rod bushing using suitable
tool.
Piston Pin Diameter
Measure diameter of piston pin using suitable tool.
Connecting Rod Bushing Oil Clearance (Small End)
(Connecting rod bushing oil clearance) = (Connecting rod bushing inner diameter) – (Piston pin outer diame-
ter)
• If the calculated value exceeds the limit, replace connecting rod assembly and/or piston and piston pin
assembly.
• If replacing piston and piston pin assembly. Refer to
EM-242, "How to Select Piston and Bearing"
.
• If replacing connecting rod assembly, follow the "CONNECTING
ROD BEARING OIL CLEARANCE" procedure to select the con-
necting rod bearing.
Standard
: 57.000 - 57.013 mm (2.2441 - 2.2446 in)
PBIC1641E
Standard
: 22.000 - 22.012 mm (0.8661 - 0.8666 in)
PBIC0120E
Standard
: 21.989 - 22.001 mm (0.8657 - 0.8662 in)
PBIC0117E
Standard
: 0.005 - 0.017 mm (0.0002 - 0.0007 in)
Limit
: 0.030 mm (0.0012 in)
PBIC0809E
EM-234
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ENGINE UNIT
Factory installed parts grading:
• Only grade “0”.
Unit: mm (in)
*: After installing in connecting rod
CYLINDER BLOCK DISTORTION
• Remove any oil, scale, gasket, sealant and carbon deposits from the cylinder block surface.
CAUTION:
Do not allow any debris to enter engine oil or engine coolant passages.
• Measure the distortion on the cylinder block upper face at some
different points in six directions with straightedge and feeler gauge.
• If it exceeds the limit, replace cylinder block.
MAIN BEARING HOUSING INNER DIAMETER
• Install lower cylinder block without installing main bearings, and
tighten lower cylinder block bolts to the specified torque. Refer to
EM-220, "Disassembly and Assembly"
for the tightening proce-
dure.
• Measure the inner diameter of main bearing housing with bore
gauge.
• If out of the standard, replace cylinder block and lower cylinder
block as assembly.
NOTE:
Cylinder block cannot be replaced as a single part, because it is
machined together with lower cylinder block.
PISTON TO CYLINDER BORE CLEARANCE
Cylinder Bore Inner Diameter
• Using bore gauge, measure cylinder bore for wear, out-of-round
and taper at six different points on each cylinder. [(X) and (Y) direc-
tions at (A), (B) and (C)] [(X) is in longitudinal direction of engine].
Grade
0
1
Connecting rod bushing
inner diameter *
22.000 - 22.006
(0.8661 - 0.8664)
22.006 - 22.012
(0.8664 - 0.8666)
Piston pin hole diameter
21.993 - 21.999
(0.8659 - 0.8661)
21.999 - 22. 005
(0.8661 - 0.8663)
Piston pin outer diameter
21.989 - 21.995
(0.8657- 0.8659)
21.995 - 22.001
(0.8659 - 0.8662)
PBIC2950E
Limit : 0.1 mm (0.004 in)
SEM123C
Standard
: 74.993 - 75.017 mm (2.9525 - 2.9534 in)
PBIC2012E
Standard inner diameter:
95.500 - 95.530 mm (3.7598 - 3.7610 in)
Out-of-round [Difference between (X) and (Y)]:
0.015 mm (0.0006 in)
Taper limit [Difference between (A) and (C)]:
0.01 mm (0.0004 in)
PBIC2955E
ENGINE UNIT
EM-235
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• If the measured value exceeds the limit, or if there are scratches
and/or seizure on the cylinder inner wall, hone or re-bore the inner
wall.
Piston Skirt Diameter
Measure the outer diameter of piston skirt with micrometer.
Piston to Cylinder Bore Clearance
Calculate by piston skirt diameter and cylinder bore inner diameter [direction (X), position (B)].
(Clearance) = (Cylinder bore inner diameter) – (Piston skirt diameter).
• If the calculated value exceeds the limit, replace piston and piston pin assembly. Refer to
.
Re-boring Cylinder Bore
1. Cylinder bore size is determined by adding piston to cylinder bore clearance to piston skirt diameter.
2. Install lower cylinder block, and tighten to the specified torque. Otherwise, cylinder bores may be distorted
in final assembly.
3. Cut cylinder bores.
NOTE:
• 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.
4. Hone cylinders to obtain the specified piston to cylinder bore clearance.
5. Measure the finished cylinder bore for out-of-round and taper.
NOTE:
Measurement should be done after cylinder bore cools down.
CRANKSHAFT MAIN JOURNAL DIAMETER
• Measure the outer diameter of crankshaft main journals with micrometer.
SEM843E
Measure point
: Distance from the top 43.03 mm (1.6941 in)
Standard
: 95.480 - 95.510 mm (3.7590 - 3.7602 in)
PBIC2956E
Standard
: 0.010 - 0.030 mm (0.0004 - 0.0012 in)
Limit
: 0.08 mm (0.0031 in)
Re-bored size calculation: D = A + B – C
where,
D: Bored diameter
A: Piston skirt diameter as measured
B: Piston to cylinder bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
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ENGINE UNIT
• If out of the standard, measure the main bearing oil clearance. Then use undersize bearing.
CRANKSHAFT PIN JOURNAL DIAMETER
• Measure the outer diameter of crankshaft pin journal with
micrometer.
• If out of the standard, measure the connecting rod bearing oil
clearance. Then use undersize bearing.
OUT-OF-ROUND AND TAPER OF CRANKSHAFT
• Measure the dimensions at four different points as shown on each
main journal and pin journal with micrometer.
• Out-of-round is indicated by the difference in the dimensions
between (X) and (Y) at (A) and (B).
• Taper is indicated by the difference in the dimensions 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
the main bearing and/or connecting rod bearing.
CRANKSHAFT RUNOUT
• Place V-block on precise flat table, and support the journals on the
both end of crankshaft.
• Place dial indicator straight up on the No. 3 journal.
• While rotating crankshaft, read the movement of the pointer on dial
indicator. (Total indicator reading)
• If it exceeds the limit, replace crankshaft.
CONNECTING ROD BEARING OIL CLEARANCE
Method by Calculation
Standard
: 69.951 - 69.975 mm (2.7540 - 2.7549 in) dia.
Standard
: 53.956 - 53.974 mm (2.1242 - 2.1250 in) dia.
PBIC0127E
Limit:
Out-of-round [Difference between (X) and (Y)]
: 0.002 mm (0.0001 in)
Taper [Difference between (A) and (B)]
: 0.002 mm (0.0001 in)
SBIA0535E
Standard : Less than 0.05 mm (0.002 in)
Limit
: 0.10 mm (0.0039 in)
SEM346D
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