Hudson 1955 Rambler, Техническое и сервисное руководство

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FIGURE 8— Checking Valve Stem to Guide
Clearance Limits—.004" Intake,
.005" Exhaust
Valve Refacing
The intake valves are faced to a 30° angle
and the exhaust valves to a 45° angle. Valves
may be refaced until remaining margin is down
to 1/32"; then the valve must be replaced.
The valve stem tip when worn can be
resurfaced and rechamfered. However, never
remove more than .010".
Valve Seat Refacing
Grind the valve seats to the following
specifications:
Seat Angle
Intake Valve 30°
Exhaust Valve 45°
Seat Width
Intake Valve 3/64"
Exhaust Valve 5/64"
Narrowing stones should be used to obtain
the proper seat widths when required.
Control seat runout to a maximum of .002"
(Fig. 9).
Valve Tappets and Push Rods
11222
The hydraulic valve tappet consists of a
body, plunger, plunger return spring, check
valve assembly, push rod socket, and lock
ring (Fig. 10).
The tappet operates in a guide bore which
has an oil passage drilled into the adjoining
main oil galleries.
When the tappet is on the heel of the cam
lobe, the plunger return spring indexes an
oil hole undercut in the plunger with the oil
supply admitted through the tappet body. Oil
FIGURE 9—Checking Valve Seat Runout
under pressure flows into the body through
the check valve assembly maintaining the
tappet fully charged. This cycle of operation
occurs when tappet leaks off some oil during
the normal valve opening events. Opening
movement of the cam lobe causes tappet body
movement, closing the check valve and trans-
mitting "zero-lash" movement of the push rod
to open the cylinder valve.
The valve tappets should be cleaned and
serviced at time of engine overhaul or
whenever excessive noise exists.
FIGURE 10— Valve Push Rod and Tappet
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T E C H N I C A L S E R V I C E M A N U A L