S e c . 6A
P age 12
G A SO LIN E ENGINES
Figure 1 — Flyw heel H o u sin g an d Adaptor Plate
(350 an d 366 V8 Engine)
P rop er functioning of the carburetor is p a r
ticu la rly e sse n tia l to control of e m issio n s. C orrect
m ixtu res for e m issio n com pliance and id le quality
have been preset. P lastic idle mixture lim iters have
been installed on the idle mixture screw s to pre
clude unauthorized adjustment. These idle lim iters
are not to be removed unless made n ecessary by
som e major carburetor repair or replacement which
affects the idle screw adjustment.
POSITIVE CRANKCASE VENTILATION VALVE
R eplace the PCV valve at 24 months or 24,000
m ile in terv a ls (w hichever o ccu rs fir st). PCV valve
h o se , when rem oved for valve replacem ent, should
be blown out with an a ir hose to make certain that
it is clean . The PCV valve should be replaced at
12 months or 12,000 m ile s (w hichever o c c u r s first)
when the v eh icle is u sed under the follow ing con-
ditionsi
• D riving in dusty conditions.
• E xten sive idling.
• Short trip operation at fr eezin g tem p er
atures (engine not thoroughly w arm ed up).
POSITIVE CRANKCASE VENTILATION
SYSTEM - HOSES AND CONNECTIONS
The PCV sy ste m should be checked for s a t is
factory operation at 12-m onth or 1 2 ,0 0 0 -m ile in
te r v a ls using a te s te r such as the AC T e ste r C T -3.
POSITIVE CRANKCASE VENTILATION
BREATHER OR FLAME ARRESTER
The breather or flam e a r r e s te r should be r e
m oved and clean ed at 12,000 m ile in te r v a ls. Im
m e r se in cleaning solven t to rem ove a ll d ep osits
and allow to drain b efore rein sta llin g .
MECHANICAL VALVE LIFTERS
Intake and exhaust v a lv es on V6 engines should
be adjusted at 12,000 m ile in terv a ls.
MANIFOLD HEAT VALVE
In -L in e engines and so m e V6 and V8 engines
a re equipped with a m anifold heat valve which should
be checked for fr e e operation. A binding valve may
be fr e e d up with G eneral M otors m anifold heat
valve lubricant or equivalent. (NEVER USE ANY
OTHER TYPE LUBRICANT.)
FLYWHEEL H O U SIN G ADAPTER
PLATE
F igure 1 show s the flyw heel housing adapter
p late u sed with 13-inch clutch on 350 and 366 V8
en gin es.
Inspect engine front and rear mountings as
part of regular engine m aintenance program . Be
su re a ll bracket attaching b olts a re kept tight.
R efer to ENGINE MOUNTINGS (SEC. 6D) for engine
mounting inform ation.
UNDERPAN
FLYWHEEL H O U SIN G
ADAPTER
EXTENSION C O VER
T-9141