(5) Check for loose or worn valve guides.
Check the internal diameter of the valve
guide with a telescope gage and a
Replace guides that are
worn to a bell-mouthed shape or guides
that have a maximum diameter of more
than 0.4082 inch.
(6) If the valve guides are worn or damaged,
chamber side, using a driver that is
slightly smaller than the external diameter
chamber side. When properly seated,
intake valve guide tops will be 14 inches
from the top of the block and exhaust
Figure 63. Checking valve seat for runout.
valve guide tops will be 19l6 inches from
arbor press or by applying light blows with
a hammer until the valve seat is resting
Do not attempt to ream the valve
against the bottom of the bore. Roll or
guides after seating them. Guides
peen the valve seat in place.
(8) Check the valve springs for cracks and
distortion. Test compression strength with
a spring tester. Compression strength
(7) Check the exhaust valve seat inserts for
must be as follows:
cracks or loose mounting. Pull out faulty
1 7/8 in. (valve closed).......
seats with new 0.010-inch oversized valve
1.521 in. (valve open)........
seats. Counterbore the valve seats to a
diameter of 1.688 to 1.687 inches. This
will provide a 0.003- to 0.005-inch press
(9) Grind the valve seats. The seat angle of
fit. Counterbore deeply enough so that
the intake valves is 30 . The seat angle
the boring tool will clean up the bottom of
of the exhaust valve is 45°. Use a dial
the bore to assure proper heat conduction
from the valve insert. Chill the valve
seats in dry ice for 20 minutes. Install the
valve seat in place with a piloted driver
Figure 64. Narrowing valve seat.
Figure 62. Pulling valve seat insert.