ENGINE - Cylinder Head and Valve9-55
3EN026
w -w===j=Margin , EN034
Squareness
IFree length
INSPECTION
CYLINDER HEADNosocAMl Check the cylinder head for cracks, damage and engine
coolant leakage.l
Remove the scale, sealing compound and carbon deposits
completely. After cleaning oil passages, apply compressedair to make certain that the passages are clear.
l Check the cylinder head gasket surface for flatness by
using a straight edge in the direction of A, B, . . . as shown. Ifthe flatness exceeds the limit in any direction, either
resurface or replace the cylinder head.
Flatness of cylinder head gasket surface:
Standard dimension
Limit
Overall height:
Limit
Caution
Less than 0.05 mm (0020 in.)
0.2 mm (008 in.)
88.5 mm (3.484 in.)
88.3 mm (3.478 in.)
If cylinder block gasket surface has already been
ground, thickness of the removed stock should be
included in the grinding limit of -0.2 mm
(-,008 in.).
VALVESNo9PGMa
(1) Check each valve for wear, damage and deformation of
head and stem at
B. Correct or replace excessively worn,
damaged or deformed valves.
(2) If stem tip A is pitted, correct with an oil stone or other
means. The correction must be limited to a minimum. Also
reface the valve.
(3) Replace the valve if the margin has decreased to less than
the limit.
Margin:
Standard dimension
Intake1.0 mm (.039 in.)
Exhaust0.7 mm (028 in.)
Limit
Intake0.7 mm (.028 in.)
Exhaust0.5 mm LO20 in.)
VALVE SPRINGSNOWGh
(1) Check the valve spring for free length and load. If they
exceed the limits, replace the spring.
(2) Using a square, check the squareness of each spring. If thespring is out of square beyond the limit, replace.
Valve spring:
Standard dimension
Free length
49.2 mm (1.937 in.)
Load274.6 N (62 Ibs.) at installed height
Installed height37.3 mm (1.469 in.)
Out of square
Less than 2”
Limit
Free length48.2 mm (1.888 in.)
Installed height38.3 mm (1.516 in.)
Out of square4”
9-114ENGINE <2.0L DOHC Engine> - Cylinder Head and Valve
Ridgewear
1 EN034Contact with
valve seat
(to be at center
6EN020
I
Freeheight
1 EN035-(3) Using a straight edge and feeler gauge, check the cylinder
head bottom surface for flatness. If it warps excessively
correct by grinding within the allowable limit.
Bottom surface distortion
Standard value:Within 0.05 mm
(.0020 in.)
Limit:‘0.2 mm
(.dO8 in.)
Grinding limit:0.2 mm
(.008 iA.)-Cylinder head height (when new):
132.0 mm (5.197 in.)
CautionThe total thickness of the stock allowed to be removed
from the cylinder head and mating cylinder block is 0.2
mm
(.008 in.) at maximum.
VALVE
NOSPGAE(1) Check the valve stem for wear (ridge wear).
(2) Check the valve stem end face for wear and dents.
(3) Check the valve seat for proper contact with the valve set.
If it is not concentric, correct the valve seat.
(4) If the margin is out of the limit, replace the valve.
Standard value:
Intake1.0 mm
(.040 in.)
Exhaust1.5 mm (.059 in.)
Limit:
Intake0.7 mm
1.028 in.)
Exhaust1.0 mm (.040 in.)
VALVE SPRING
NOSPGBC
Measure the free height of the spring and replace if it is outof the limit.
Standard value: 48.3 mm (1.902
in.)Limit: 47.3 mm (1.862 in.)
Check the spring for squareness and replace if the limit is
exceeded.Standard value: Less than
1.5’Limit:
4”
