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
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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
EM-104
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CYLINDER HEAD
Revision: 2006 January2006 M35/M45
Cylinder Head Distortion
NOTE:
When performing this inspection, cylinder block distortion should be also checking. Refer to EM-143, "
CYLIN-
DER BLOCK DISTORTION" .
1. Using a scraper, wipe off oil, scale, gasket, sealant and carbon deposits from surface of cylinder head.
CAUTION:
Do not allow gasket fragments to enter engine oil or engine coolant passages.
2. At each of several locations on bottom surface of cylinder head,
measure the distortion in six directions.
If it exceeds the limit, replace cylinder head.
INSTALLATION
1. Install new cylinder head gaskets.
2. Turn crankshaft until No. 1 piston is set at TDC.
Crankshaft key should line up with the right bank cylinder cen-
ter line as shown in the figure.
3. Install cylinder head follow the steps below to tighten cylinder
head bolts in numerical order as shown in the figure with cylin-
der head bolts wrench (commercial service tool).
CAUTION:
If cylinder head bolts re-used, check their outer diameters
before installation. Refer toEM-103, "
Cylinder Head Bolts
Outer Diameter" .
a. Apply new engine oil to threads and seat surfaces of cylinder
head bolts.
b. Tighten all cylinder head bolts.
c. Completely loosen all cylinder head bolts.
CAUTION:
In step “c”, loosen bolts in reverse order of that indicated in
the figure.
d. Tighten all cylinder head bolts.Limit : 0.1 mm (0.004 in)
SEM861E
SEM532G
: 98.1 Nꞏm (10 kg-m, 72 ft-lb)
: 0 Nꞏm (0 kg-m, 0 ft-lb)
: 39.2 Nꞏm (4.0 kg-m, 29 ft-lb)
PBIC2057E
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 —
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CYLINDER HEAD
Revision: 2006 January2006 M35/M45
Disassembly and AssemblyNBS004NU
COMPONENTS
DISASSEMBLY
1. Remove spark plug with spark plug wrench (commercial service tool).
2. Remove valve lifter.
Identify installation positions, and store them without mixing them up.
3. Remove valve collet.
Compress valve spring with the valve spring compressor, the
attachment and the adapter (SST). Remove valve collet with
a magnet hand.
CAUTION:
When working, take care not to damage valve lifter holes.
4. Remove valve spring retainer, valve spring and valve spring seat.
5. Push valve stem to combustion chamber side, and remove valve.
Identify installation positions, and store them without mixing them up.
1. Valve lifter 2. Valve collet 3. Valve spring retainer
4. Valve spring 5. Valve oil seal 6. Valve spring seat
7. Valve guide 8. Spark plug 9. Spark plug tube
10. Cylinder head (right bank) 11. Valve seat 12. Valve (EXH)
13. Valve (INT) 14. Cylinder head (left bank)
PBIC2637E
PBIC1803E
CYLINDER HEAD
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6. Remove valve oil seal using the valve oil seal puller (SST).
7. If valve seat must be replaced, refer to EM-110, "
VALVE SEAT REPLACEMENT" .
8. If valve guide must be replaced, refer to EM-109, "
VALVE GUIDE REPLACEMENT" .
9. Remove spark plug tube, as necessary.
Using a pliers, pull spark plug tube out of cylinder head.
CAUTION:
Take care not to damage cylinder head.
Once removed, spark plug tube will be deformed and cannot be reused. Do not remove it unless
absolutely necessary.
ASSEMBLY
1. When valve guide is removed, install it. Refer to EM-109, "VALVE GUIDE REPLACEMENT" .
2. When valve seat is removed, install it. Refer to EM-110, "
VALVE SEAT REPLACEMENT" .
3. Install new valve oil seals as follows:
a. Apply new engine oil on valve oil seal joint and seal lip.
b. Install with the valve oil seal drift (SST) to match dimension in
the figure.
4. Install valve spring seat.
5. Install valve.
Larger diameter valves are for intake side.
NOTE:
Larger diameter valves are for intake side.
6. Install valve spring (uneven pitch type).
Install narrow pitch end (paint mark) to cylinder head side
(valve spring seat side).
7. Install valve spring retainer.
PBIC0884E
Height “H” (Without valve spring seat installed)
Intake and exhaust : 14.3 - 14.9 mm (0.563 - 0.587 in)
PBIC2769E
Paint mark collar
: Blue
SEM085D
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
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4. Heat cylinder head to 110 to 130C (230 to 266F) by soaking in
heated oil.
5. Using the valve guide drift (commercial service tool), press valve
guide from camshaft side to the dimensions as in the figure.
WA R N I N G :
Cylinder head contains heat. When working, wear protec-
tive equipment to avoid getting burned.
6. Using the valve guide reamer (commercial service tool), apply
reamer finish to valve guide.
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 sur-
face.
Check if the contact area band is continuous all around the cir-
cumference.
If not, grind to adjust valve fitting and check again. If the contact-
ing surface still has “NG” conditions even after the re-check,
replace valve seat. Refer to EM-110, "
VALVE SEAT REPLACE-
MENT" .
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 EM-156, "
Va l v e S e a t" .
CAUTION:
Prevent to 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