Inspection and Reconditioning (Rev 1/97)
55
3. After grinding the valve seats, install the valves in their
respective valve seats and check the valve depth of
each. Replace any valve that has been ground and now
has a valve depth over the wear limit. Replace any
valve seat that has a new valve installed and still has a
valve depth over the wear limit.
4. Check the width of the valve seats with a caliper.
5. Use Prussian Blue or a similar dye to check the align-
ment of the each valve seat and valve face. The valve
seat should contact the middle of the valve face.
6. Use 15 and 70 degree grinding stones to size and align
the valve seats to meet the width specifications (refer to
Specifications), and alignment recommendation above.
Valve Seat Replacement
1. Use a standard valve seat removal tool to remove a
valve seat from the cylinder head.
NOTE: If a valve seat removal tool is not available,
use a welding torch to heat the valve seat insert red
hot at two spots directly across from each other.
Allow the valve seat insert to cool and contract for 3 to
5 minutes.
Pry the valve seat insert out of the cylinder head with
a small pry bar.
2. Clean any carbon or other foreign material out of the
valve seat insert bore in the cylinder head.
3. Measure the outside diameter of the new valve seat
insert and the inside diameter of the valve seat insert
bore. The valve seat insert should be .002 to .004 in.
(0.05 to 0.10 mm) larger than the valve seat insert bore
for a proper interference fit.
4. Chill the valve seat insert and install it with a valve seat
installation tool.
5. Grind the new valve seats after installation.
Valve Springs
1. Clean and inspect the valve springs. Replace valve
springs that are cracked, or significantly scratched or
damaged.
2. Measure the free length of the valve springs with a cali-
per. Replace any valve springs that are shorter than the
wear limits (refer to Specifications).
Measuring Valve Spring Free Length
3. Check the inclination of the valve springs with a
square. Replace any valve springs with inclinations
larger than the maximum limits (refer to Specifica-
tions).
Checking Valve Spring Inclination
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