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IDLER GEAR OIL CLEARANCE
IMeasure the inner diameter (d1) of idler gear shaft hole.
Standard: 26.000 - 26.020 mm (1.0236 - 1.0244 in)
I Measure the outer diameter (d
2) of idler shaft.
Standard: 25.967 - 25.980 mm (1.0223 - 1.0228 in)
I Calculate gear clearance.
Clearance = d
1þd2Standard: 0.023 - 0.053 mm (0.0009 - 0.0021 in)
Installation
1. Install cylinder head gasket.
ICylinder head gasket to be installed is selected by its thickness
through the following procedure.
When replacing gasket only
IInstall gasket with same thickness as the one removed.
I Gasket thickness is identified by the number of notches located
on rear-left side.
Grade Gasket thickness*
mm (in) No. of notches
1 0.65 (0.0256) 1
2 0.70 (0.0276) 2
*: Thickness of gasket tightened with head bolts
I The number of notches can be checked at the position shown
in the figure before cylinder head is removed. (It is necessary
to remove exhaust manifold.)
When repairing/replacing the following
IWhen the top of cylinder block or crankshaft pin/journal is
ground, or
I When cylinder block, piston, connecting rod, or crankshaft is
replaced
1) Move piston toward TDC.
2) Position dial indicator on cylinder block as shown in the figure, and adjust the needle to ª0º.
3) Move dial indicator stand aside, and position the dial indicator to the measuring point as shown in the figure.
4) Rotate crankshaft slowly, and read the value on dial indicator at piston's maximum height.
5) Repeat above procedure at 2 positions of each cylinder (8 positions in total for 4 cylinders), and select the appropriate
gasket by comparing the maximum crown depression with the
table.
FEM057
YEM031
FEM059
FEM060
CYLINDER HEADZD
Inspection (Cont'd)
EM-54
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Unit: mm (in)
GradePiston crown
depression Gasket thick-
ness*1 No. of notches
1 Less than þ0.078
(þ0.0031)*2 0.65 (0.0256) 1
2 More than þ0.078
(þ0.0031)*3 0.70 (0.0276) 2
*1: Thickness of gasket tightened with head bolts
*2: Indicates values such as þ0.080 mm (þ0.0031 in).
*3: Indicates values such as þ0.075 mm (þ0.0030 in).
2. Install idler gear and idler shaft.
I
Check that the counter marks with cam gear, ªAAº and ªBBº, are
located on the front side of the engine.
Refer to EM-52.
CAUTION:
Since idler gear cannot be installed or removed with cylinder
head assembly mounted on the engine because of interfer-
ence with gear case, make sure that there are no reverse
installations or uninstalled parts.
3. Install cylinder head assembly.
1) Attach gasket onto the rear of gear case.
2) Install O-ring to the rear of gear case.
3) Align cylinder head assembly with dowel pin of cylinder block and install.
CAUTION:
I Make sure the O-ring does not fall off. Be careful not to
drop the O-ring.
I Do not damage gasket located at the front.
4. Position cylinder head assembly close to the rear of the gear case.
1) Install cylinder head bolts to the front and rear of cylinder head respectively, and tighten to the specified torque.
:40-49N ×m (4.0 - 5.0 kg-m, 29 - 36 ft-lb)
2) Loosen cylinder head bolts completely.
3) Install gear case mounting bolts to 2 positions shown by arrows in the figure, and tighten to the specified torque.
: Less than 9.8 N ×m (1.0 kg-m, 87 in-lb)
5. Tighten cylinder head bolts in the order indicated in the figure.
1) Apply engine oil to installation bolt threads and washers.
2) Tighten bolts to 98 to 102 N×m (10.0 to 10.5 kg-m, 73 to 75 ft- lb).
3) Loosen bolts completely until the torque becomes 0 N ×m(0
kg-m, 0 in-lb).
CAUTION:
For procedure 3), loosen bolts in the reverse order as indi-
cated in the figure.
4) Tighten bolts to 40 to 44 N ×m (4.0 to 4.5 kg-m, 29 to 32 ft-lb).
5) Tighten bolts at the angle of 90 to 95É (target is 95É). (Angle tightening)
FEM061
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FEM055
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Installation (Cont'd)
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6) Once again, tighten bolts at the angle of 90 to 95É (target is95É). (Angle tightening)
CAUTION:
Perform the following procedure to check turning angle of
angle tightening, and do not judge by visual check.
ANGLE TIGHTENING PROCEDURE
With protractor
I Make counter marks on the bolt head of cylinder head and cyl-
inder head surface with paint, and check the turning angle.
With angle wrench (SST)
ICheck the turning angle using angle indicator of angle wrench.
6. Loosen gear case mounting bolts which were tightened in 3) of procedure 4, retighten them to the specified torque.
7. Install glow plug.
I 2 different types (manufacturers) of glow plugs are provided in
parallel. (Refer to the figure for identification.)
I Do not install 2 different types of glow plugs in the engine. Make
sure that the same glow plugs are installed.
I Using reamer, remove the carbon adhering to the installation
hole of glow plug, and install glow plug.
FEM063
FEM064
CYLINDER HEADZD
Installation (Cont'd)
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Page 148 of 1833
8. Install oil return pipe to the rear side of the cylinder head.
IWhen reinstalling a stud bolt, apply Three Bond 1207C (KP510
00150) to the thread of the bolt.
Disassembly
1. Remove adjusting shims and valve lifters.
Check the installation positions, and keep them to avoid being
confused.
2. Using valve spring compressor (SST), compress valve spring. Using magnetic hand, remove valve collets.
3. Remove valve spring retainers and valve springs.
4. Remove valves as pressing valve stems toward combustion chamber.
I Before removing the valve, check the valve guide clearance.
(Refer to EM-58.)
I Check installation positions, and keep them to avoid being con-
fused.
I Refer to the figure for intake/exhaust valve positions. (Intake
and exhaust valve driving cams are provided alternately for
each camshaft.)
FEM081
SEM361G
FEM010
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Installation (Cont'd)
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5. Remove valve oil seals using valve oil seal puller (SST).
6. Remove valve spring seats.
7. Before removing valve spring seats, perform valve seat contactcheck. (Refer to EM-60.)
8. Before removing valve guides, perform valve guide clearance check. (Refer to below.)
Inspection
CYLINDER HEAD DISTORTION
Using straightedge and feeler gauge, check the bottom of the cyl-
inder head for distortion. Limit: 0.2 mm (0.008 in)
VALVE DIMENSION
Using micrometer, measure the dimensions of each part.
Standard
Unit: mm (in)
Intake valve Exhaust valve
L 113.5 (4.4685)113.5 (4.4685)
T 1.5 (0.059)1.5 (0.059)
f d 6.962 - 6.977
(0.2741 - 0.2747) 6.945 - 6.960
(0.2734 - 0.2740)
f D 31.9 - 32.1
(1.256 - 1.264) 29.9 - 30.1
(1.177 - 1.185)
a (degree) 45É00¢- 45É30¢ 45É00¢- 45É30¢
VALVE GUIDE CLEARANCE
IPerform the inspection before removing valve guides.
I Check that the valve stem diameter is within specifications.
I Push valve approximately 25 mm (0.98 in) toward combustion
chamber, move valve toward dial indicator to measure valve
movement.
I Valve guide clearance is 1/2 of movement on dial indicator.
FEM065
FEM066
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FEM068
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Disassembly (Cont'd)
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Unit: mm (in)
StandardLimit
Intake 0.023 - 0.056
(0.0009 - 0.0022) 0.18 (0.0071)
Exhaust 0.040 - 0.073
(0.0016 - 0.0029) 0.10 (0.0039)
I
If the measured value exceeds the limit, replace valve guide.
VALVE GUIDE REPLACEMENT
IThere is no setup for oversized valve guide.
1. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF) in oil bath.
2. Using valve guide drift (multi-purpose tool: for 7.0 mm dia.), tap valve guides out from the combustion chamber side.
3. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF) in oil bath.
4. Using valve guide drift (multi-purpose tool: for 7.0 mm dia.), press fit valve guides from camshaft side, referring to the
dimension shown in the figure.
5. Using valve guide reamer (multi-purpose tool), perform ream- ing to the press-fitted valve guides.Reaming specifications: Intake/Exhaust7.000 - 7.018 mm (0.2756 - 0.2763 in)
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Inspection (Cont'd)
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VALVE SEAT CONTACT
Check valve for any evidence of pitting at valve contact surface,
and reseat or replace if worn out excessively.
IWhen repairing valve seats, check valve and valve guide
for wear beforehand. If worn, replace them. Then correct
valve seat.
I The cutting should be done with both hands for uniform
cutting.
VALVE SEAT REPLACEMENT
IWhen removing valve seat, replace it with oversized [0.5 mm
(0.0020 in)] valve seat.
1. Cut valve seat to make it thin, and pull it out.
2. Machine cylinder head inner diameter at valve seat installation position.Machining dimension: Intake33.500 - 33.515 mm (1.3189 - 1.3195 in) dia.
Exhaust 31.995 - 32.010 mm (1.2596 - 1.2602 in) dia.
3. Heat cylinder head to approximately 110 to 130ÉC (230 to 266ÉF) in oil bath.
4. After cooling valve seats sufficiently with dry ice, press fit it to cylinder head.
CAUTION:
Do not touch the cooled valve seats directly by hand.
5. Using valve seat cutter (multi-purpose tool), finish processing referring to the dimensions shown in the figure.
CAUTION:
When using valve seat cutter, grasp cutter handle with both
hands, press cutter onto contacting face all around, and cut
thoroughly. If cutter is pressed unevenly or repeatedly, the
valve seat surface may be damaged.
6. Using compound, perform valve fitting.
7. Check again to make sure that contacting status is satisfactory.
FEM073
FEM074
FEM075
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Inspection (Cont'd)
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For details of values (q1toq10), refer to EM-87, ªValve Seatº in
ªSERVICE DATA AND SPECIFICATIONS (SDS)º.
VALVE SPRING RIGHT ANGLE
Position a straightedge to valve spring, turn the spring, and mea-
sure the maximum clearance value between top surface of spring
and the straightedge Limit: 2.4 mm (0.094 in)
VALVE SPRING FREE LENGTH AND COMPRESSIVE
LOAD
Using valve spring tester, check the following.Free length: 55.43 mm (2.1823 in)
Installation height: 40.8 mm (1.6063 in)
Installation load: 180 - 206 N (18.4 - 21.0 kg, 40.6 -
46.3 lb)
Height at valve open: 32.3 mm (1.2717 in)
Load at valve open: 336 - 372 N (34.3 - 37.9 kg, 75.6 -
83.6 lb)
Assembly
1. Install valve guides, referring to EM-60, ªVALVE SEATREPLACEMENTº.
2. Install valve seats, referring to EM-60, ªVALVE SEAT CON- TACTº.
3. Using valve oil seal drift (SST), install valve oil seals referring to the dimension shown in the figure.
I The figure shows the dimension before valve spring seats are
installed.
4. Install valve spring seats.
5. Install valves.
I Install the valves with bigger openings to intake valve side.
I Note that valve layout here is different from that of conventional
the engine.
YEM035
FEM077
FEM078
FEM079
CYLINDER HEADZD
Inspection (Cont'd)
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