Page 1577 of 2267
2. If it exceeds the limit, check valve to valve guide clearance.
a. Measure valve stem diameter and valve guide inner diameter.
b. Calculate valve to valve guide clearance.
Valve to valve guide clearance = Valve guide inner diam-
eter þ Valve stem diameter.
c. Check that clearance is within specification.
Unit: mm (in)
Standard Limit
Intake0.020 - 0.050
(0.0008 - 0.0020)0.1 (0.004)
Exhaust0.040 - 0.070
(0.0016 - 0.0028)0.1 (0.004)
IIf it exceeds the limit, replace valve and remeasure clearance.
IIf limit is still exceeded after replacing valve, replace valve
guide.
VALVE GUIDE REPLACEMENTNCEM0019S091. To remove valve guide, heat cylinder head to 110 to 130ÉC
(230 to 266ÉF).
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.
SEM938C Micrometer
SEM008AOil
SEM931C
CYLINDER HEADQG
Inspection (Cont'd)
EM-37
Page 1578 of 2267

3. Ream cylinder head valve guide hole.
Valve guide hole diameter
(for service parts):
Intake & Exhaust
9.685 - 9.696 mm (0.3813 - 0.3817 in)
4. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF) and press
service valve guide into cylinder head.
Projection ªLº:
11.5 - 11.7 mm (0.453 - 0.461 in)
5. Ream valve guide.
Finished size:
Intake & Exhaust
5.500 - 5.515 mm (0.2165 - 0.2171 in)
VALVE SEATSNCEM0019S10Check valve seats for pitting at contact surface. Resurface or
replace if excessively worn.
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.
REPLACING VALVE SEAT FOR SERVICE PARTSNCEM0019S111. Bore out old seat until it collapses. Set machine depth stop so
that boring cannot contact the bottom face of seat recess in
cylinder head.
2. Ream cylinder head recess.
Reaming bore for service valve seat
Oversize [0.5 mm (0.020 in)]:
Refer to SDS, EM-182.
Use the valve guide center for reaming to ensure valve seat
will have the correct fit.
SEM932C Suitable reamer
MEM096A
SEM932C Suitable reamer
SEM934C
SEM795A
.Recess diameter
CYLINDER HEADQG
Inspection (Cont'd)
EM-38
Page 1579 of 2267

3. Heat cylinder head to 110 to 130ÉC (230 to 266ÉF).
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-179.
6. After cutting, lap valve seat with abrasive compound.
7. Check valve seating condition.
Seat face angle ªaº:
45É15¢- 45É45¢
Contacting width ªWº:
Intake
1.06 - 1.34 mm (0.0417 - 0.0528 in)
Exhaust
1.20 - 1.68 mm (0.0472 - 0.0661 in)
8. Use a depth gauge to measure the distance ªLº 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 correct it. If the distance is longer, replace the
valve seat.
Valve seat resurface limit:
Intake
35.95 - 36.55 mm (1.4154 - 1.4390 in)
Exhaust
35.92 - 36.52 mm (1.4142 - 1.4378 in)
VALVE DIMENSIONSNCEM0019S12Check dimensions of each valve. Refer to SDS, EM-182 for dimen-
sions.
When valve head has been worn down to 0.5 mm (0.020 in) in
margin thickness, replace valve.
Grinding allowance for valve stem tip is 0.2 mm (0.008 in) or
less.
VALVE SPRINGNCEM0019S13SquarenessNCEM0019S13011. Measure dimension ªSº.
Out-of-square ªSº:
Less than 1.75 mm (0.0689 in)
2. If it exceeds the limit, replace spring.
SEM008AOil
SEM892B
AEM343
SEM188A T (Margin thickness)
SEM288A S (Out-of-square)
CYLINDER HEADQG
Inspection (Cont'd)
EM-39
Page 1580 of 2267

PressureNCEM0019S1302Check valve spring pressure at specified spring height.
Pressure:
Standard
370.0 N (37.73 kg, 83.19 lb) at 23.64 mm
(0.9307 in)
Limit
More than 347.8 N (35.46 kg, 78.19 lb) at
23.64 mm (0.9307 in)
If it exceeds the limit, replace spring.
VALVE LIFTER AND VALVE SHIMNCEM0019S161. Check contact and sliding surfaces for wear or scratches.
2. Check diameter of valve lifter and valve lifter guide bore.
Valve lifter outside diameter:
29.960 - 29.975 mm (1.1795 - 1.1801 in)
Lifter guide inside diameter:
30.000 - 30.021 mm (1.1811 - 1.1819 in)
Clearance between valve lifter and valve lifter guide:
0.025 - 0.065 mm (0.0010 - 0.0024 in)
If it exceeds the limit, replace valve lifter or cylinder head which
exceeds the standard diameter tolerance.
Valve ClearanceNCEM0041CHECKINGNCEM0041S01Check valve clearance while engine is warm and not running.
1. Remove rocker cover.
2. Remove all spark plugs.
3. Set No. 1 cylinder at TDC on its compression stroke.
IAlign pointer with TDC mark on crankshaft pulley.
ICheck that valve lifters on No. 1 cylinder are loose and valve
lifters on No. 4 are tight.
EM113
SEM160D
SEM161D
SEM920F
SEM921F Pointer
Timing
mark
Crankshaft pulley
CYLINDER HEADQG
Inspection (Cont'd)
EM-40
Page 1581 of 2267

IIf not, turn crankshaft one revolution (360É) and align as
described above.
4. Check only those valves shown in the figure.
IUsing a feeler gauge, measure clearance between valve lifter
and camshaft.
IRecord any valve clearance measurements which are out of
specification. They will be used later to determine the required
replacement adjusting shim.
Valve clearance for checking (Hot):
Intake
0.21 - 0.49 mm (0.008 - 0.019 in)
Exhaust
0.30 - 0.58 mm (0.012 - 0.023 in)
5. Turn crankshaft one revolution (360É) and align mark on crank-
shaft pulley with pointer.
6. Check only those valves shown in the figure.
IUse the same procedure as mentioned in step 4.
7. If all valve clearances are within specification, install the fol-
lowing parts:
IRocker cover
IAll spark plugs
ADJUSTINGNCEM0041S02Adjust valve clearance while engine is cold.
1. Turn crankshaft. Position cam lobe upward on camshaft for
valve that must be adjusted.
2. Place Tool (A) around camshaft as shown in figure.
Before placing Tool (A), rotate notch toward center of cylinder
head. (See figure.) This will simplify shim removal later.
CAUTION:
Be careful not to damage cam surface with Tool (A).
SEM922F INT
EXH
Engine front
No. 4 No. 3 No. 2 No. 1
.SEM139D
SEM923F INT
EXH
Engine front
No. 1
No. 2
No. 3 No. 4
SEM941F Tool (A) KV10115110
Notch
CYLINDER HEADQG
Valve Clearance (Cont'd)
EM-41
Page 1582 of 2267

3. Rotate Tool (A) so that valve lifter is pushed down.
4. Place Tool (B) between camshaft and valve lifter to retain valve
lifter.
CAUTION:
ITool (B) must be placed as close to camshaft bracket as
possible.
IBe careful not to damage cam surface with Tool (B).
5. Remove Tool (A).
6. Remove adjusting shim using a small screwdriver and a mag-
netic finger.
7. Determine replacement adjusting shim size using the following
formula.
IUse a micrometer to determine thickness of removed shim.
ICalculate thickness of new adjusting shim so valve clearance
comes within specified values.
R = Thickness of removed shim
N = Thickness of new shim
M = Measured valve clearance
Intake:
N=R+[Mþ0.37 mm (0.0146 in)]
Exhaust:
N=R+[Mþ0.40 mm (0.0157 in)]
Shims are available in 50 sizes from 2.00 mm (0.0787 in) to 2.98
mm (0.1173 in), in steps of 0.02 mm (0.0008 in).
ISelect the closest size shim to the calculated thickness. Refer
to chart in SDS, EM-180.
SEM924F Tool (A)
KV10115110
SEM925F Tool (B)
KV10115120
Tool (A)
SEM144D Magnetic
finger
.Tool (B)
SEM145D
AEM236 Indicate
T
1= 2.800 mm
(0.1102 in)
Shim
CYLINDER HEADQG
Valve Clearance (Cont'd)
EM-42
Page 1583 of 2267

8. Install new shim using a suitable tool.
IInstall with the surface on which the thickness is stamped
facing down.
9. Place Tool (A) as explained in steps 2 and 3.
10. Remove Tool (B).
11. Remove Tool (A).
12. Recheck valve clearance.
Valve clearance:
Unit: mm (in)
For adjusting For checking
HotCold* (reference
data)Hot
Intake0.32 - 0.40
(0.013 - 0.016)0.25 - 0.33
(0.010 - 0.013)0.21 - 0.49
(0.008 - 0.019)
Exhaust0.37 - 0.45
(0.015 - 0.018)0.32 - 0.40
(0.013 - 0.016)0.30 - 0.58
(0.012 - 0.023)
*: At a temperature of approximately 20ÉC (68ÉF)
Whenever valve clearances are adjusted to cold specifications, check that
the clearances satisfy hot specifications and adjust again if necessary.
AssemblyNCEM00201. Install valve component parts.
IAlways use new valve oil seal. Refer to EM-29.
IBefore installing valve oil seal, install valve spring seat.
IAfter installing valve components, tap valve stem tip with
a plastic hammer to assure a proper fit.
IInstall valve spring (narrow pitch at both ends of spring)
with either end toward cylinder head.
InstallationNCEM00211. Before installing cylinder head gasket, apply a continuous
bead of liquid gasket to mating surface of cylinder block.
2. Install cylinder head gasket.
IWhen installing cylinder head with manifolds, use new
cylinder head gasket.
SEM146D Tool (B)
Suitable tool
SEM147D Tool (B)
Tool (A)
AEM293 Narrow pitch
Wide pitch
Narrow pitch
SEM899F
Liquid gasket
2.0 - 3.0 mm
(0.079 - 0.118 in) dia.
Engine
front
CYLINDER HEADQG
Valve Clearance (Cont'd)
EM-43
Page 1584 of 2267

3. Install cylinder head with manifolds.
IBe sure to install washers between bolts and cylinder
head.
IDo not rotate crankshaft and camshaft separately, or
valves will strike piston heads.
IApply new engine oil to cylinder head bolt threads and
seat surfaces.
ITightening procedure
paTighten bolts to 29 N×m (3 kg-m, 22 ft-lb).
pbTighten bolts to 59 N×m (6 kg-m, 43 ft-lb).
pcLoosen bolts completely.
pdTighten bolts to 29 N×m (3 kg-m, 22 ft-lb).
peTurn bolts 50 to 55 degrees clockwise or if angle
wrench is not available, tighten bolts to 59 4.9 N×m (6 0.5
kg-m, 43 3.6 ft-lb).
pfTightening bolts (11 - 14) to 6.3 to 8.3 N×m (0.64 to 0.85
kg-m, 55.8 to 73.5 in-lb).
Tightening torque N×m (kg-m, ft-lb)
abcde,f
Bolts
(1-10)29
(3, 22)59
(6, 43)0
(0, 0)29
(3, 22)50-55
degrees or
59 4.9
(6 0.5,
43 3.6
ft-lb)
Bolts
(11-14)ÐÐÐÐ6.3 - 8.3
(0.64 -
0.85, 55.8 -
73.5 in-lb)
4. Install camshaft.
IMake sure camshafts are aligned as shown in figure.
SEM877A Cylinder head bolt washer
Cylinder head side
SEM900F Engine front
Tighten in numerical order.
SEM614EC
Tightening torque
N´m (kg-m, ft-lb)
59 (6, 43)
29 (3, 22)
SEM901F Intake Exhaust
SEM902F Intake Exhaust
Knock pin
Knock pin
CYLINDER HEADQG
Installation (Cont'd)
EM-44