Nissan Titan A60. Manual — part 479
ENGINE UNIT
EM-101
< UNIT DISASSEMBLY AND ASSEMBLY >
C
D
E
F
G
H
I
J
K
L
M
A
EM
N
P
O
• Install the main bearing caps with the main bearings removed, and
tighten the bolts to the specified torque. Refer to
.
• Measure inside diameter of main bearing housing.
• If out of the standard, replace cylinder block and main bearing
caps as an assembly.
NOTE:
These components must be replaced as a single unit, because
they were processed together.
PISTON TO CYLINDER BORE CLEARANCE
Cylinder Bore Diameter
• Measure the cylinder bore for wear, out-of-round and taper at six
different points on each cylinder (
″X″ and ″Y″ directions at ″A″, ″B″
and
″C″).
NOTE:
When determining cylinder bore grade, measure cylinder bore at
"B" position.
• If measured value exceeds the repair limit, or if there are scratches and/or seizure on the cylinder inner wall,
hone or bore the inner wall.
Piston Skirt Diameter
• Measure piston skirt diameter using suitable tool.
Standard
: 68.944 - 68.968 mm (2.7143 - 2.7153 in)
PBIC1643E
PBIC0123E
Standard diameter:
98.000 - 98.030 mm (3.8583 - 3.8594 in)
Wear limit:
0.20 mm (0.0079 in)
Out-of-round (Difference between
″X″ and ″Y″):
Limit: 0.015 mm (0.0006 in)
Taper limit (Difference between
″A″ and ″C″):
Limit: 0.010 mm (0.0004 in)
PBIC0124E
Standard
: 97. 980 - 98. 010 mm (3.8575 - 3.8587 in)
PBIC0125E
EM-102
< UNIT DISASSEMBLY AND ASSEMBLY >
ENGINE UNIT
• Measure point
″H″.
Piston to Cylinder Bore Clearance
• Calculate by using diameter of the piston skirt and the cylinder bore diameter (direction X, position B).
(Clearance) = (Cylinder bore diameter) – (piston skirt diameter)
• If calculation exceeds the limit, replace piston/piston pin assembly.
Reboring Cylinder Bore
1. Cylinder bore size is determined by adding piston-to-bore clearance to piston diameter “A”.
2. Install main bearing caps, and tighten them to the specified torque. Otherwise, cylinder bores may be dis-
torted in final assembly.
3. Cut the 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 one 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-bore clearance.
5. Measure finished cylinder bore for out-of-round and taper.
NOTE:
Measurement should be done after cylinder bore cools down.
CRANKSHAFT JOURNAL DIAMETER
• Measure diameter of crankshaft journals.
• If measurement is out of standard, measure the main bearing oil clearance. Then use the undersize bearing.
CRANKSHAFT PIN DIAMETER
Distance from the top
: 39 mm (1.54 in)
KBIA2545E
Standard
: 0.010 - 0.030 mm (0.0004 - 0.0012 in)
Limit
: 0.08 mm (0.0031 in)
Rebored size calculation: D = A +B - C
where,
D: Bored diameter
A: Piston diameter as measured
B: Piston - to - bore clearance (standard value)
C: Honing allowance 0.02 mm (0.0008 in)
Standard
: 63.940 - 63.964 mm (2.5173 - 2.5183 in)
ENGINE UNIT
EM-103
< UNIT DISASSEMBLY AND ASSEMBLY >
C
D
E
F
G
H
I
J
K
L
M
A
EM
N
P
O
• Measure diameter of crankshaft pin using suitable tool.
• If measurement is out of standard, measure connecting rod bear-
ing oil clearance. Then use undersize bearing.
OUT-OF-ROUND AND TAPER OF CRANKSHAFT
• Measure dimensions at four different points as shown on each
journal and pin.
• Out-of-roundness is indicated by the difference in dimension
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 measured value exceeds the standard, correct or replace crankshaft.
• If corrected, measure the bearing oil clearance of the corrected journal or pin. Then select the main bearing
or connecting rod bearing.
CRANKSHAFT RUNOUT
• Place a V-block on a precise flat table to support the journals on
both ends of the crankshaft.
• Measure at No. 3 journal using suitable tool.
• While rotating crankshaft, read the movement of the pointer.
• Half of the movement shows the runout.
• If measurement exceeds the limit, replace crankshaft.
CONNECTING ROD BEARING OIL CLEARANCE
Method of Measurement
• Install connecting rod bearings to the connecting rod and cap. Tighten connecting rod bolts to the specified
EM-89, "Disassembly and Assembly"
.
Measure inside diameter of connecting rod bearing.
(Oil clearance) = (Inside diameter of connecting rod bearing) –
(Crankshaft pin diameter)
• If clearance cannot be adjusted within the standard, grind crank-
shaft pin and use undersized bearing. Refer to
.
Method of Using Plastigage
Standard
: 53.956 - 53.974 mm (2.1243 - 2.1250 in)
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)
PBIC1685E
Limit
: Less than 0.05 mm (0.002 in)
PBIC0129E
Standard
: 0.020 - 0.039 mm (0.0008 - 0.0015 in)
Limit
: 0.055 mm (0.0022 in)
PBIC1642E
EM-104
< UNIT DISASSEMBLY AND ASSEMBLY >
ENGINE UNIT
• Remove oil and dust on the crankshaft pin and surfaces of each
bearing completely.
• Cut a plastigage slightly shorter than the bearing width, and place
it in the crankshaft axial direction, avoiding oil holes.
• Install the connecting rod bearings to the connecting rod and con-
necting rod bearing cap, and tighten the connecting rod bolts to the
specified torque.
CAUTION:
Do not rotate crankshaft with plastigage installed.
• Remove the connecting rod bearing cap and bearings. Measure
the plastigage width using the scale on the plastigage bag.
NOTE:
The procedure when the measured value exceeds the repair limit is the same as that described in “Method
of Measurement”.
MAIN BEARING OIL CLEARANCE
Method of Measurement
• Install the main bearings to the cylinder block and main bearing
cap. Measure the main bearing inside diameter with the bearing
cap bolts tightened to the specified torque. Refer to
.
(Oil clearance) = (Inside diameter of main bearing) – (Crankshaft
journal diameter)
• If measured value exceeds the repair limit, select main bearings referring to the main bearing inside diame-
ter and crankshaft journal diameter, so that the oil clearance satisfies the standard. Refer to
Method of Using Plastigage
• Remove oil and dust on the crankshaft journal and 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 main bearings to the cylinder block and main bearing
cap, and tighten the main bearing bolts to the specified torque.
CAUTION:
Do not rotate crankshaft with plastigage installed.
• Remove bearing cap and bearings. Measure plastigage width
using the scale on the plastigage bag.
NOTE:
The procedure when the measured value exceeds the repair limit
is the same as that described in “Method of Measurement”.
CRUSH HEIGHT OF MAIN BEARING
KBIA2550E
Standard:
No. 1 and 5 journals
: 0.001 - 0.011 mm (0.00004 - 0.0004 in)
No. 2, 3 and 4 journals
: 0.007 - 0.017 mm (0.0003 - 0.0007 in)
Limit:
No.1 and 5 journals
: 0.021 mm (0.0008 in)
No. 2, 3 and 4 journals
: 0.027 mm (0.0011 in)
PBIC1644E
KBIA2551E
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