Air Injection Reactor S Y S T E M - GMC 4000 Series Service Manual

Sec. 6M
Page 338
FUEL SYSTEM— GASOLINE ENGINES
V A C U U M LINE
(/
D IA P H R A G M EX T E N SIO N
V A C U U M IDLE STO P
Figure 3 0 — Vacuum Idle Stop-Bendix-Strom berg
Carburetor (W W Series)
The C.C.S.-M. system is that system which
increases combustion efficiency, and combustion
efficiency reduces the hydrocarbon and carbon
monoxide em issions. The complete effectiveness
of this system , as well as full power and perform­
ance, is dependent upon the correct idle speed,
ignition timing, and idle fuel mixture.
IMPORTANT: The C.C.S.-M. system consists
of no additional components, other than a specially
calibrated carburetor and a vacuum idle stop.
V A C U U M LINE
j j i 7 ^ D IA P H R A G M E X T E N S IO N
V A C U U M I D L E T r O p S f e < 'l * * * H 9 i M » » f t
Figure 31 — Vacuum Idle Stop-Bendix-Strom berg
Carburetor (W W C Series)
G M C S E R V I C E M A N U A L
CARBURETOR
vehicles functions and operates the same as all
other Bendix-Stromberg carburetors used on V6
engines. But under no circum stances should they
be interchanged with, or replaced by another type
carburetor.
-M. engines, refer to "Idle and Mixture Adjust­
ments" previously covered in this section.
VACUUM IDLE STOP
(Refer to Figs. 30 and 31)
P L U N G E R *
-M. equipped engines to prevent engine "dieseling"
(engine operation after ignition switch is turned
off).
etor with a bracket and acts upon the throttle plates
of the carburetor in the same manner as an idle
setscrew . When the engine is started, engine vac­
uum acts upon the diaphragm in the idle stop unit
and the plunger is pushed to its full extended p osi­
tion. The plunger acts upon the throttle lever and
sets the throttle plates in a position to achieve the
specified idle rpm. When the ignition switch is
turned "OFF," engine vacuum is reduced and the
plunger retracts into the idle stop unit. The result
is the throttle plate closes to a lower position
which is controlled by the idle speed screw. At this
point, the throttle plate is open only enough to a l­
low the engine to run well below normal idle rpm.
refer to "Idle and Mixture Adjustment" previously
covered in this section.
found only on In-line engines, covered by this man­
ual, sold in the state of California.
tion pump (with necessary brackets and drive at­
tachments), air injection tube, diverter valve,
check valve, and air manifold assembly, tubes and
hoses necessary to connect the various components.
P L U N G E R
tegral filter, com presses the air and injects it
through the air manifolds, hoses, and injection
tubes into the exhaust system in the area of the
exhaust valves. The fresh air ignites and burns
the unburned portion of the exhaust gases in the
exhaust system, thus minimizing exhaust contam­
inations.
The carburetor used on C.C.S.-M. equipped
NOTE: For carburetor adjustments on C.C.S.
A vacuum idle stop unit is used on all C.C.S.
The idle stop unit is mounted to the carbur­
NOTE: For adjustment of the vacuum idle stop,
AIR INJECTION REACTOR
SYSTEM (A.I.R.)
NOTE: The A.I.R. system (figs. 32 and 33) is
The A.I.R. system consists of: The air injec­
OPERATION
The air injection pump (fig. 34) with an in­