CYLINDER HEAD
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CYLINDER HEADPFP:11041
On-Vehicle ServiceNBS004NR
CHECKING COMPRESSION PRESSURE
1. Warm up engine thoroughly. Then, stop it.
2. Release fuel pressure. Refer to EC-98, "
FUEL PRESSURE RELEASE" .
3. Disconnect fuel pump fuse to avoid fuel injection during mea-
surement.
4. Remove engine cover with power tool. Refer to EM-19, "
INTAKE MANIFOLD COLLECTOR" .
5. Remove ignition coil and spark plug from each cylinder. Refer to EM-42, "
IGNITION COIL" and EM-43,
"SPARK PLUG (PLATINUM-TIPPED TYPE)" .
6. Connect engine tachometer (not required in use of CONSULT-ll).
7. Install compression gauge with an adapter (commercial service
tool) onto spark plug hole.
Use the adapter whose picking up end inserted to spark plug
hole is smaller than 20 mm (0.79 in) in diameter. Otherwise, it
may be caught by cylinder head during removal.
8. With accelerator pedal fully depressed, turn ignition switch to “START” for cranking. When the gauge
pointer stabilizes, read the compression pressure and the engine rpm. Perform these steps to check each
cylinder.
Compression pressure:
Unit: kPa (kg/cm2 , psi) /rpm
CAUTION:
Always use a fully changed battery to obtain the specified engine speed.
SBIA0466E
PBIC0900E
SBIA0533E
Standard Minimum Deference limit between cylinders
1,275 (13.0, 185) / 300 981 (10.0, 142) / 300 98 (1.0, 14) / 300
EM-102
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CYLINDER HEAD
Revision: 2006 January2006 M35/M45
If the engine speed is out of the specified range, check battery liquid for proper gravity. Check the
engine speed again with normal battery gravity.
If compression pressure is below minimum value, check valve clearances and parts associated with
combustion chamber (valve, valve seat, piston, piston ring, cylinder bore, cylinder head, cylinder head
gasket). After the checking, measure compression pressure again.
If some cylinder has low compression pressure, pour small amount of engine oil into the spark plug hole
of the cylinder to re-check it for compression.
–If the added engine oil improves the compression, piston rings may be worn out or damaged. Check
piston rings and replace if necessary.
–If the compression pressure remains at low level despite the addition of engine oil, valves may be mal-
functioning. Check valves for damage. Replace valve or valve seat accordingly.
If two adjacent cylinders have respectively low compression pressure and their compression remains
low even after the addition of engine oil, cylinder head gaskets are leaking. In such a case, replace cyl-
inder head gaskets.
9. After inspection is completed, install removed parts.
10. Start the engine, and make sure that the engine runs smoothly.
11. Perform trouble diagnosis. If DTC appears, erase it. Refer to EC-100, "
TROUBLE DIAGNOSIS" .
ComponentsNBS004NS
Removal and InstallationNBS004NT
REMOVAL
1. Remove camshaft. Refer to EM-84, "CAMSHAFT" .
NOTE:
It is also possible to perform the following steps 2 and 3 just before removing camshaft.
1. Engine rear lower slinger 2. Cylinder head (left bank) 3. Cylinder head bolt
4. Cylinder head (right bank) 5. Cylinder head gasket (right bank)6. Cylinder head gasket (left bank)
7. Oil level gauge guide
SBIA0581E
CYLINDER HEAD
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e. Turn all cylinder head bolts 90 degrees clockwise (angle tighten-
ing).
CAUTION:
Check the tightening angle by using the angle wrench
(SST). Avoid judgment by visual inspection without SST.
Check tightening angle indicated on the angle wrench indica-
tor plate.
f. Turn all cylinder head bolts 90 degrees clockwise again (angle
tightening).
4. After installing cylinder head, measure distance between front
end faces of cylinder block and cylinder head (left and right
banks).
If measured value is out of the standard, re-install cylinder
head.
5. Install in the reverse order of removal after this step.
INSPECTION AFTER INSTALLATION
Inspection for Leaks
The following are procedures for checking fluids leak, lubricates leak and exhaust gases leak.
Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-12, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
Use procedure below to check for fuel leakage.
–Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.
–Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gases, or any oil/fluids
including engine oil and engine coolant.
Bleed air from lines and hoses of applicable lines, such as in cooling system.
After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to the
specified level, if necessary.
Summary of the inspection items:
* Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.
PBIC0888E
Standard : 14.1 - 14.9 mm (0.555 - 0.587 in)
EMQ0662D
Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Other oils and fluid* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gases — Leakage —
CYLINDER HEAD
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Valve Guide Clearance
(Valve guide clearance) = (Valve guide inner diameter) – (Valve stem diameter)
If the calculated value exceeds the limit, replace valve and/or valve guide. When valve guide must be
replaced, refer to EM-109, "
VALVE GUIDE REPLACEMENT" .
VALVE GUIDE REPLACEMENT
When valve guide is removed, replace with oversized [0.2 mm (0.008 in)] valve guide.
1. To remove valve guide, heat cylinder head to 110 to 130
C (230
to 266
F) by soaking in heated oil.
2. Drive out valve guide with a press [under a 20 kN (2 ton, 2.2 US
ton, 2.0 lmp ton) pressure] or a hammer and the valve guide drift
(commercial service tool).
WAR NING :
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
3. Using the valve guide reamer (commercial service tool), ream
cylinder head valve guide hole.Standard
Intake and Exhaust : 6.000 - 6.018 mm (0.2362 - 0.2369 in)
Valve guide clearance:
Standard
Intake : 0.020 - 0.053 mm (0.0008 - 0.0021 in)
Exhaust : 0.030 - 0.063 mm (0.0012 - 0.0025 in)
Limit
Intake : 0.08 mm (0.003 in)
Exhaust : 0.10 mm (0.004 in)
SEM008A
SEM931C
Valve guide hole diameter (for service parts):
Intake and exhaust
: 10.175 - 10.196 mm (0.4006 - 0.4014 in)
SEM932C
CYLINDER HEAD
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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 266F) by soaking in
heated oil.
4. Provide valve seats cooled well with dry ice. Force fit valve seat into cylinder head.
WAR NING :
Cylinder head contains heat. When working, wear protective equipment to avoid getting burned.
CAUTION:
Avoid directly touching cold valve seats.
5. Using the valve seat cutter set (commercial service tool) or valve
seat grinder, finish seat to the specified dimensions. Refer to
EM-156, "
Va l v e S e a t" .
CAUTION:
When using the 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 with cutter or cutting many different times may
result in stage valve seat.
6. Using compound, grind to adjust valve fitting.
7. Check again for normal contact. Refer to EM-110, "
VA LV E S E AT C O N TA C T" .
VALVE SPRING SQUARENESS
Set a try square along the side of valve spring and rotate spring.
Measure the maximum clearance between the top of spring and
try square.
If it exceeds the limit, replace valve spring.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-114
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ENGINE ASSEMBLY
Revision: 2006 January2006 M35/M45
REMOVAL
Outline
At first, remove the engine and the transmission assembly with front suspension member from vehicle down-
ward. Then separate the engine from transmission.
Preparation
1. Release fuel pressure. Refer to EC-98, "FUEL PRESSURE RELEASE" .
2. Drain engine coolant from radiator. Refer to CO-11, "
Changing Engine Coolant" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
3. Disconnect both battery cables. Refer to SC-4, "
BATTERY" .
4. Remove the following parts:
Engine room cover (RH and LH); Refer toEM-14, "ENGINE ROOM COVER" .
Engine cover; Refer to EM-19, "INTAKE MANIFOLD COLLECTOR" .
Front road wheel and tires (power tool)
Front and rear engine undercover (power tool)
Cowl top cover (RH); Refer to EI-18, "COWL TOP" .
Air duct and air cleaner case assembly; EM-17, "AIR CLEANER AND AIR DUCT" .
5. Discharge refrigerant from A/C circuit. Refer to ATC-151, "
REFRIGERANT LINES" .
6. Remove radiator hoses (upper and lower). Refer to CO-14, "
RADIATOR" .
Engine Room LH
1. Disconnect heater hose from vehicle-side, and fit a plug onto hose end to prevent engine coolant leak.
2. Disconnect wire bonding (between vehicle to left bank cylinder head).
3. Disconnect A/C piping from A/C compressor, and temporarily fasten it on vehicle with a rope. Refer to
AT C - 1 5 1 , "
REFRIGERANT LINES" .
4. Disconnect brake booster vacuum hose.
Engine Room RH
1. Disconnect battery positive cable at vehicle side and temporarily fasten it on engine.
2. Disconnect grounding cable.
3. Disconnect fuel feed hose (with damper) and EVAP hose. Refer to EM-45, "
FUEL INJECTOR AND FUEL
TUBE" .
CAUTION:
Fit plugs onto disconnected hoses to prevent fuel leak.
4. Remove reservoir tank of power steering oil pump and piping from vehicle, and temporarily secure them
on engine. Refer to PS-29, "
POWER STEERING OIL PUMP" .
CAUTION:
When temporarily securing, keep the reservoir tank upright to avoid a fluid leak.
Vehicle inside
Follow procedure below to disconnect engine room harness connectors at passenger room side, and tempo-
rarily secure them on engine.
1. Remove passenger-side kicking plate, dash side finisher, and glove box. Refer to EI-37, "
BODY SIDE
TRIM" and IP-10, "INSTRUMENT PANEL ASSEMBLY" .
2. Disconnect engine room harness connectors at unit sides TCM, ECM and other.
3. Disengage intermediate fixing point. Pull out engine room harnesses to engine room side, and temporarily
secure them on engine.
CAUTION:
When pulling out harnesses, take care not to damage harnesses and connectors.
After temporarily securing, cover connectors with vinyl or similar material to protect against for-
eign material adhesion.
ENGINE ASSEMBLY
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INSPECTION AFTER INSTALLATION
Inspection for Leaks
The following are procedures for checking fluids leak, lubricates leak and exhaust gases leak.
Before starting engine, check oil/fluid levels including engine coolant and engine oil. If less than required
quantity, fill to the specified level. Refer to MA-12, "
RECOMMENDED FLUIDS AND LUBRICANTS" .
Use procedure below to check for fuel leakage.
–Turn ignition switch “ON” (with engine stopped). With fuel pressure applied to fuel piping, check for fuel
leakage at connection points.
–Start engine. With engine speed increased, check again for fuel leakage at connection points.
Run engine to check for unusual noise and vibration.
Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gases, or any oil/fluids
including engine oil and engine coolant.
Bleed air from lines and hoses of applicable lines, such as in cooling system.
After cooling down engine, again check oil/fluid levels including engine oil and engine coolant. Refill to the
specified level, if necessary.
Summary of the inspection items:
* Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc. Item Before starting engine Engine running After engine stopped
Engine coolant Level Leakage Level
Engine oil Level Leakage Level
Other oils and fluid* Level Leakage Level
Fuel Leakage Leakage Leakage
Exhaust gases — Leakage —
ENGINE ASSEMBLY
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If items or work required are not covered by the engine section, refer to the applicable sections.
Always use the support point specified for lifting.
Use either 2-pole lift type or separate type lift as best you can. If board-on type is used for
unavoidable reasons, support at rear axle jacking point with transmission jack or similar tool
before starting work, in preparation for the backward shift of center of gravity.
For supporting points for lifting and jacking point at rear axle, refer to GI-42, "Garage Jack and
Safety Stand and 2-Pole Lift" .
REMOVAL
Outline
At first, remove the engine, the transmission assembly, the transfer assembly and the front final drive assem-
bly with front suspension member from vehicle downward. Then separate the engine, the transmission assem-
bly, the transfer and the front final drive assembly.
Preparation
1. Release fuel pressure. Refer to EC-98, "FUEL PRESSURE RELEASE" .
2. Drain engine coolant from radiator. Refer to CO-11, "
Changing Engine Coolant" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
3. Disconnect both battery terminals. Refer to SC-4, "
BATTERY" .
4. Remove the following parts:
Engine room cover (RH and LH); Refer to EM-14, "ENGINE ROOM COVER" .
Engine cover; Refer to EM-19, "INTAKE MANIFOLD COLLECTOR" .
Front road wheel and tires (power tool)
Front and rear engine undercover (power tool)
Front cross bar; Refer to FSU-23, "FRONT SUSPENSION ASSEMBLY" .
Cowl top cover (RH); Refer to EI-18, "COWL TOP" .
Air duct and air cleaner case assembly; EM-17, "AIR CLEANER AND AIR DUCT" .
5. Discharge refrigerant from A/C circuit. Refer to ATC-151, "
REFRIGERANT LINES" .
6. Remove radiator hoses (upper and lower). Refer to CO-14, "
RADIATOR" .
Engine Room LH
1. Disconnect heater hose from vehicle-side, and fit a plug onto hose end to prevent engine coolant leak.
2. Disconnect wire bonding (between vehicle to left bank cylinder head).
3. Disconnect A/C piping from A/C compressor, and temporarily fasten it on vehicle with a rope. Refer to
AT C - 1 5 1 , "
REFRIGERANT LINES" .
4. Disconnect brake booster vacuum hose.
Engine Room RH
1. Disconnect battery positive cable vehicle side and temporarily fasten it on engine.
2. Disconnect grounding cables.
3. Disconnect fuel feed hose (with damper) and EVAP hose. Refer to EM-45, "
FUEL INJECTOR AND FUEL
TUBE" .
CAUTION:
Fit plugs onto disconnected hoses to prevent fuel leak.
4. Remove reservoir tank of power steering oil pump and piping from vehicle, and temporarily secure them
on engine. Refer to PS-29, "
POWER STEERING OIL PUMP" .
CAUTION:
When temporarily securing, keep the reservoir tank upright to avoid a fluid leak.
Vehicle inSide
Follow procedure below to disconnect engine room harness connectors at passenger room side, and tempo-
rarily secure them on engine.