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14
FIGURE 15
INTAKE
6 cyl.
8 cyl.
A - 45°
45°
B - 1.831"
1.500"
C - .1135"
.1135"
D - .0495"
.036"
E - .083"
.0765"
F - .016"
.005"
G - .054"
.0575"
H - 1-11/16"
1-3/8"
NOTE: Seat diameter of valve head must be
concentric with valve stem within .002" total
indicator reading. Valve stem end should be
ground flat and square with axis within .002"
total indicator reading.
A valve head face that is not concentric with the
part of the shim that operates in the guide will
contact the valve sat on only a small part of the total
circumference. It will slap, rattle, leak compression
and affect valve timing.
Valve seats in the cylinder block should be cut
with a suitable valve seat cutter. The seats should be
cut only enough to remove pits and surface glaze. If
seats are made too wide in. the cleaning up process,
use a cutter with the proper size pilot to obtain
proper valve seat width. When reducing the seat at
cylinder head face use a 15° cutter and a 75° cutter
at port end.
EXHAUST
6 cyl.
8 cyl.
45°
45°
1.561"
1.375"
.1525"
.1295"
.0496"
.036"
.103"
.0935"
.008"
.0045"
.075"
.078"
1-3/8"
1-7/32"
A properly refaced valve will contact the valve
seat throughout its entire circumference and the
valve stem will "float" in the guide, free from valve
stem friction.
NOTE: The best valve grinding and aligning job
will go for naught if care is not used when tight-
ening the cylinder head. Always use a torque
wrench and tighten the cap screws or stud nuts in
the sequence recommended to the following
torque specifications 60-65 foot lbs. for both alu-
minum and cast iron heads 6 cylinder engines,
40-45 foot pounds for all 8 cylinder engines.
VALVE GUIDES - PAGE 3-43
Before reconditioning a valve seat it is important
that the valve guides be checked for wear.
Valve guides that are worn .003" more than the
clearances recommended in the following chart they
should be replaced.
6 CYLINDER
Valve Stem
Valve Guide
8 CYLINDER
Valve Stem
Valve Guide
Valve guides can be removed upward through the
valve seat opening with a suitable puller.
Valve guides can be properly installed with the
J-883-A Valve Guide Installer. The installer consists
of the driver handle, stop collar, and two pilots
calibrated to insure that the guides are driven to the
proper depth. On 8 cylinder engines the top of the
valve guide should be 15/16" below the top face of
the block for both intake and exhaust. See Figure 16.
EXHAUST
INTAKE
.3407
.3417
.3437
.3437
EXHAUST
INTAKE
.3397
.3412
.3437
.3437
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