oil INFINITI QX4 2001 Factory Service Manual
Page 1678 of 2395
SEM948E
ReplacementNBEM0015CAUTION:
When removing the oil pans, oil pump assembly and timing
chain from engine, first remove the camshaft position sensor
(PHASE), CVTC sensor and the crankshaft position sensors
(REF)/(POS) from the assembly.
Be careful not to damage sensor edges.
VALVE OIL SEALNBEM0015S011. Remove timing chain. Refer to ªRemoval, EM-23.
2. Remove camshaft brackets and camshaft. Refer to
ªDisassemblyº, EM-41.
3. Remove valve lifters and shims.
4. Remove valve spring with Tool.
5. Reinstall any parts removed in reverse order of removal.
Before removing valve spring, fix valve as follows.
Method A:
Piston concerned should be set at TDC to prevent valve
from falling.
SEM826E
Method B:
Remove spark plug, then install air hose adapter into
spark plug hole and apply air pressure to hold valves in
place. Apply a pressure of 490 kPa (5 kg/cm
2, 71 psi).
SEM983D
Method C:
Install spark plug with suitable washer into spark plug
hole from combustion chamber side.
SEM827E
6. Remove valve oil seal.
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OIL SEAL
Replacement
EM-35
Page 1679 of 2395
SEM828E
7. Apply engine oil to new valve oil seal and install it with Tool.
SEM715A
OIL SEAL INSTALLATION DIRECTIONNBEM0015S02IInstall new oil seal in the direction shown in the figure.
FRONT OIL SEALNBEM0015S031. Remove the following parts:
IEngine undercover
ISuspension member stay
IDrive belts
ICrankshaft position sensor (REF)
Be careful not to damage sensor edge.
ICrankshaft pulley
IRadiator
ICooling fan
SEM829E
2. Remove front oil seal using a suitable tool.
Be careful not to scratch front cover.
3. Apply engine oil to new oil seal and install it using a suitable
tool.
SEM830E
REAR OIL SEALNBEM0015S041. Remove transmission. Refer to AT-277, ªRemovalº.
2. Remove drive plate.
3. Remove oil pan. Refer to EM-15.
4. Remove rear oil seal retainer.
OIL SEAL
Replacement (Cont'd)
EM-36
Page 1680 of 2395
SEM831E
5. Remove old liquid gasket using scraper.
IRemove old liquid gasket from the bolt hole and thread.
SEM832EA
6. Apply liquid gasket to rear oil seal retainer.
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OIL SEAL
Replacement (Cont'd)
EM-37
Page 1681 of 2395
ComponentsNBEM0016
SEM441GA
1. Oil filler cap
2. Rocker cover
3. Camshaft bracket
4. Camshaft
5. PCV valve
6. Cylinder head
7. Blow-by hose8. Spark plug
9. Valve
10. Valve spring seat
11. Valve spring
12. Valve spring retainer
13. Valve collet14. Valve lifter
15. Shim
16. Chain tensioner
17. Spring
18. Tensioner sleeve
19. CVTC valve
CYLINDER HEAD
Components
EM-38
Page 1682 of 2395
CAUTION:
IWhen installing camshafts, chain tensioners, oil seals, or
other sliding parts, lubricate contacting surfaces with new
engine oil.
IApply new engine oil to threads and seat surfaces when
installing cylinder head, camshaft sprocket, crankshaft
pulley, and camshaft bracket.
IAttach tags to valve lifters so as not to mix them up.
RemovalNBEM00171. Remove engine from vehicle. Refer to EM-57, ªRemoval and
Installationº.
2. Remove exhaust manifolds in reverse order of installation.
Refer to EM-13, ªExhaust Manifoldº.
3. Place engine on a work stand.
4. Remove aluminum oil pan. Refer to EM-15, ªRemovalº.
5. Remove timing chain. Refer to EM-23, ªRemovalº.
SEM964F
6. Remove intake manifold in reverse order of installation. Refer
to ªTIGHTENING PROCEDURESº, EM-12.
7. Remove water outlet.
SEM442G
8. Remove rear timing chain case bolts.
ILoosen in numerical order as shown in the figure.
SEM168FA
9. Remove rear timing chain case.
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CYLINDER HEAD
Components (Cont'd)
EM-39
Page 1684 of 2395
SEM444G
14. Remove RH and LH camshaft chain tensioners from cylinder
head.
SEM859E
SEM860E
15. Remove cylinder head bolts.
ICylinder head bolts should be loosened in two or three
steps.
IA warped or cracked cylinder head could result from
removing in incorrect order.
SEM863E
16. Remove cylinder head.
DisassemblyNBEM0043Remove valve component parts.
Refer to EM-35, ªVALVE OIL SEALº.
ICheck the clearance before removing the valve guide. Refer to
EM-43, ªVALVE GUIDE CLEARANCEº.
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CYLINDER HEAD
Removal (Cont'd)
EM-41
Page 1687 of 2395
SEM938C
2. If it exceeds the limit, check valve to valve guide clearance.
a. Measure valve stem diameter and valve guide inner diameter.
b. Check that clearance is within specification.
Valve to valve guide clearance limit:
Intake 0.08 mm (0.0031 in)
Exhaust 0.1 mm (0.004 in)
c. If it exceeds the limit, replace valve or valve guide.
SEM008A
VALVE GUIDE REPLACEMENTNBEM0019S091. To remove valve guide, heat cylinder head to 110 to 130ÉC
(230 to 266ÉF) by soaking in heated oil.
SEM931C
2. Drive out valve guide with a press [under a 20 kN (2 ton, 2.2
US ton, 2.0 Imp ton) pressure] or hammer and suitable tool.
SEM932C
3. Ream cylinder head valve guide hole.
Valve guide hole diameter (for service parts):
10.175 - 10.196 mm (0.4006 - 0.4014 in)
SEM950E
4. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF) and press
service valve guide onto cylinder head.
Projection ªLº:
12.6 - 12.8 mm (0.496 - 0.504 in)
5. Ream valve guide.
Finished size:
6.000 - 6.018 mm (0.2362 - 0.2369 in)
CYLINDER HEAD
Inspection (Cont'd)
EM-44
Page 1688 of 2395
SEM934C
VALVE SEATSNBEM0019S10Check valve seats for any evidence of pitting at valve contact
surface, and reseat or replace if it has worn out excessively.
IBefore repairing valve seats, check valve and valve guide
for wear. If they have worn, replace them. Then correct
valve seat.
IUse both hands to cut uniformly.
SEM795A
REPLACING VALVE SEAT FOR SERVICE PARTSNBEM0019S111. 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.
2. Ream cylinder head recess for service valve seat.
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)
Be sure to ream in circles concentric to the valve guide
center.
This will enable valve seat to fit correctly.
SEM892B
3. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF) by soaking
in heated oil.
4. Press fit valve seat until it seats on the bottom.
5. Cut or grind valve seat using suitable tool to the specified
dimensions as shown in SDS (EM-79).
6. After cutting, lap valve seat with abrasive compound.
7. Check valve seating condition.
Seat face angle ªaº: 45É
Contacting width ªWº:
Intake 1.09 - 1.31 mm (0.0429 - 0.0516 in)
Exhaust 1.29 - 1.51 mm (0.0508 - 0.0594 in)
SEM621F
8. Use a depth gauge to measure the distance between the
mounting surface of the cylinder head spring seat and the
valve stem end. If the distance is shorter than specified, repeat
step 5 above to adjust it. If it is longer, replace the valve seat
with a new one.
Valve seat resurface limit ªLº:
Intake 41.07 - 41.67 mm (1.6169 - 1.6405 in)
Exhaust 41.00 - 41.60 mm (1.6142 - 1.6378 in)
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CYLINDER HEAD
Inspection (Cont'd)
EM-45
Page 1690 of 2395
SEM867E
Lifter guide bore diameter:
35.000 - 35.021 mm (1.3780 - 1.3788 in)
SEM085D
AssemblyNBEM00201. Install valve component parts.
IAlways use new valve oil seal. Refer to ªVALVE OIL
SEALº, EM-35.
IBefore installing valve oil seal, install valve spring seat.
IInstall valve spring (uneven pitch type) with its narrow
pitch side toward cylinder head side (paint mark).
IAfter installing valve component parts, tap valve stem tip with
plastic hammer to assure a proper fit.
SEM891E
InstallationNBEM00211. Before installing rear timing chain case, remove old liquid gas-
ket from mating surface using a scraper.
IAlso remove old liquid gasket from mating surface of cylinder
block.
SEM161F
IRemove old liquid gasket from the bolt hole and thread.
SEM892E
2. Before installing cam bracket, remove old liquid gasket from
mating surface using a scraper.
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CYLINDER HEAD
Inspection (Cont'd)
EM-47
Page 1691 of 2395
SEM532G
3. Before installing the cylinder head gasket, be sure that No. 1
cylinder is at TDC.
IAt this time, the crankshaft key should face toward the right
bank.
SEM445G
4. Install cylinder heads with new gaskets.
IDo not rotate crankshaft and camshaft separately, or
valves will strike piston heads.
SEM957E
CAUTION:
Cylinder head bolts are tightened by plastic zone tightening
method. Whenever the size difference between d1 and d2
exceeds the limit, replace them with new ones.
Limit (d1 - d2):
0.11 mm (0.0043 in)
ILubricate threads and seat surfaces of the bolts with new
engine oil.
CYLINDER HEAD
Installation (Cont'd)
EM-48