Pontiac FIREBIRD 1972 Service Manual page 578

6-66 1972 PONTIAC SERVICE MANUAL
a tray and a cover. One chamber is for cleaning solvent
and the other is for kerosene. Whenever the tank is not
being used (and when parts are soaking), the cover should
be closed.
Before placing tray of parts in cleaning solvent, first
immerse it in kerosene chamber to remove as much
engine oil as possible. (This reduces contamination of
solvent, thus prolonging its useful life.)
Submerge tray in cleaning solvent and allow to soak
for approximately one hour. More time may be re-
quired depending on varnish condition and effective-
ness of solvent. Light agitation of tray in solvent at
10-15 minute intervals will hasten cleaning action.
After varnish has dissolved or has been sufficiently
softened to permit removal by wiping, suspend tray
above solvent, utilizing hooks on tray handles. Allow
tray and parts to drain for a brief period.
Rinse tray of parts in kerosene chamber to cut solvent
and to avoid injury to hands (from solvent).
Wipe out tank cover and place tray of parts on cover
in front of tank (Fig. 6-106). A shop tow1 under tray
and clean paper on remainder of cover will ensure
cleanliness. (Absolute cleanliness can be assured if
each lifter is inspected and assembled after cleaning
before proceeding to the next lifter).
Working on one lifter at a time and using clean,
lint-free cloths, thoroughly wipe off lifter parts. Clean
plunger and external and internal surfaces of body
with hard wiping action. A bristle brush may be used
to clean internal surface of lifter body.
CAUTION: Do not use wire brush or sand pa-
per, since damage to machined surface is likely.
Inspect lifter body. Both inner and outer surfaces of
lifter body should be inspected for scoring. Lifter
assembly should be replaced if body is roughly
scored, grooved, or galled. Inspect cam contact sur-
face on lower end of lifter body. Replace lifter assem-
bly if this surface is excessively worn, galled or
otherwise damaged.
Inspect lifter plunger. Using magnifying glass, in-
spect check ball seat for defects. Inspect outer surface
of plunger for scratches or scores. Small score marks
with rough, satiny finish will cause plunger to seize
when hot but operate normally when cool. Defects in
check ball seat or scores or scratches on outer surface
of plunger which may be felt with fingernail are
causes for replacing lifter assemby. This rule does not
apply to slight edge which may sometimes be present
where lower end of plunger extends below the ground
inner surface of body. This edge is not detrimental
unless it is sharp or burred.
A blackened appearance is not a malfunctioning con-
dition. Sometimes discoloration serves to highlight
slight grinder chatter marks and give the outer sur-
face of plunger a ridged or fluted appearance. This
condition will not cause improper operation, there-
fore, it may be disregarded.
9. Inspect push rod seat for roughness and make sure
that hole in center is open.
10. Carefully examine lifter ball for nicks, imbedded
material or other defects which would prevent proper
seating. Such defects may cause intermittently noisy
lifter operation. Also inspect plunger face of ball re-
tainer for excessive wear.
ASSEMBLE
CAUTION: All parts must be absolutely clean
when assembling a hydraulic lifter. Since lint
and dust may adhere to parts they should not
be blown o f f with air or wiped with cloths. A 1 1
parts should be rinsed in clean kerosene and
assembled without drying. A small container
with clean kerosene (separate from cleaning
tank) should be used for each set oflifiers being
o verhauled.
Fig. 6-109 shows the relative position of component parts
of valve lifters. The recommended procedure for assembly
is given in the following steps.
1. Rinse plunger spring and ball retainer and position
retainer in spring.
2. Rinse lifter ball and place in retainer. (On high ball
lifters, the lifter ball spring will be positioned in re-
tainer before lifter ball).
3. Rinse plunger and place on retainer so that seat on
plunger mates with ball.
4. Invert plunger with parts assembled thus far and,
after rinsing lifter body, install body over spring and
plunger.
I
PUIH ROL SEAT
Fig.
6-109 Hydraulic Valve Lifter
-
Exploded View