Nissan Xterra. Manual — part 367
EM-96
< REMOVAL AND INSTALLATION >
[VQ40DE]
CYLINDER HEAD
4. Heat cylinder head to 110
° to 130°C (230° to 266°F) by soaking
in heated oil.
5. Press valve guide from camshaft side to the dimensions as
shown using suitable tool.
WARNING:
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
6. Apply reamer finish to valve guide using suitable tool.
VALVE SEAT CONTACT
• After confirming that the dimensions of valve guides and valves are
within the specifications, perform this procedure.
• Apply prussian blue (or white lead) onto contacting surface of valve
seat to check the condition of the valve contact on the surface.
• Check if the contact area band is continuous all around the circum-
ference.
• If not, grind to adjust valve fitting and check again. If the contacting
surface still has “NG” conditions even after the re-check, replace
valve seat.
VALVE SEAT REPLACEMENT
When valve seat is removed, replace with oversized [0.5 mm (0.020 in)] valve seat.
1. Bore out old seat until it collapses. Boring should not continue beyond the bottom face of the seat recess
in cylinder head. Set the machine depth stop to ensure this. Refer to
.
CAUTION:
Do not scratch cylinder head by excessive boring.
SEM008A
Projection “L”
Intake and exhaust
: 12.6 - 12.8 mm (0.496 - 0.504 in)
SEM950E
Standard:
Intake and exhaust
: 6.000 - 6.018 mm (0.2362 - 0.2369 in)
SEM932C
SBIA0322E
CYLINDER HEAD
EM-97
< REMOVAL AND INSTALLATION >
[VQ40DE]
C
D
E
F
G
H
I
J
K
L
M
A
EM
N
P
O
2. Ream cylinder head recess diameter for service valve seat.
• Be sure to ream in circles concentric to valve guide center.
This will enable valve to fit correctly.
3. Heat cylinder head to 110
° to 130°C (230° to 266°F) by soaking
in heated oil.
4. Provide valve seats cooled well with dry ice. Force fit valve seat into cylinder head.
WARNING:
• Cylinder head contains heat. When working, wear protective equipment to avoid getting burned.
CAUTION:
• Avoid directly touching cold valve seats.
5. Finish seat to the specified dimensions using suitable tool. Refer
.
CAUTION:
When using valve seat cutter, firmly grip cutter handle with
both hands. Then, press on the contacting surface all
around the circumference to cut in a single drive. Improper
pressure on cutter or cutting many different times may
result in staged valve seat.
6. Using compound, grind to adjust valve fitting.
7. Check again for normal contact.
VALVE SPRING SQUARENESS
• Set try square along the side of valve spring and rotate spring.
Measure the maximum clearance between the top face of spring
and try square.
• If it exceeds the limit, replace valve spring.
VALVE SPRING DIMENSIONS AND VALVE SPRING PRESSURE LOAD
Oversize [0.5 mm (0.020 in)]
Intake
: 38.500 - 38.516 mm (1.5157 - 1.5164 in)
Exhaust
: 32.700 - 32.716 mm (1.2874 - 1.2880 in)
SEM795A
SEM008A
SEM934C
Limit
: 2.1 mm (0.083 in)
PBIC0080E
EM-98
< REMOVAL AND INSTALLATION >
[VQ40DE]
CYLINDER HEAD
• Check valve spring pressure at the specified spring height.
• If the installation load or load with valve open is out of the standard, replace valve spring.
Standard:
Intake and exhaust
Free height
: 47.07 mm (1.8531 in)
Installation height
: 37.00 mm (1.4567 in)
Installation load
: 166 - 188 N (16.9 - 19.2 kg, 37 - 42 lb)
Height during valve open
: 27.20 mm (1.0709 in)
Load with valve open
: 373 - 421 N (38.0 - 42.9 kg, 84 - 95 lb)
SEM113
ENGINE ASSEMBLY
EM-99
< UNIT REMOVAL AND INSTALLATION >
[VQ40DE]
C
D
E
F
G
H
I
J
K
L
M
A
EM
N
P
O
UNIT REMOVAL AND INSTALLATION
ENGINE ASSEMBLY
Exploded View
INFOID:0000000009484489
Removal and Installation
INFOID:0000000009484490
WARNING:
• Situate vehicle on a flat and solid surface.
• Place chocks at front and back of rear wheels.
• For engines not equipped with engine slingers, attach proper slingers and bolts described in PARTS
CATALOG.
1.
Rear engine mounting insulator 4WD 2. Rear engine mounting insulator 2WD 3. LH engine mounting bracket (upper)
4.
LH heat shield plate
5. LH engine mounting insulator
6. LH engine mounting bracket (lower)
7.
RH engine mounting bracket (lower)
8. RH engine mounting insulator
9. RH heat shield plate
10. RH engine mounting bracket (upper)
AWBIA0721GB
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст