Pontiac FIREBIRD 1972 Service Manual page 757

6D-14 1972 PONTIAC SERVICE MANUAL
PERIODIC SERVICE
All hoses, lines and connections should be visually in-
spected each time the car is lubricated.
Replace canister base filter every 12 months or 12,000
miles (Fig. 6D-20). The filter can be serviced by (1) replac-
ing only the filler, or (2) replacing the filter and cap as an
assembly. The procedure for the second method is to
remove the original filter from the bottom of the canister
and discard along with .the original cap after removing the
'hose. Install the hose on the new filter and cap assembly.
Snap the filter, cap and hose assembly into the bottom of
the canister.
,
I
NOTE:
Second method is applicable only to X
. .
Fig. 60-20 Replacing Canister Filter
series.
AIR INJECTION REACTOR SYSTEM
GENERAL DESCRIPTION
The Air Injection Reactor (A.I.R.) System (Fig. 6D-21)
used on 250 CID L-6 engines with automatic transmission
consists of: the air injection pump (with necessary brack-
ets and drive attachments), an air diverter valve, and
check valve, and hoses necessary to connect the various
components.
Carburetors and distributors for engines with the A.I.R.
System are designed, particularly, for these engines; there-
fore, they should not be interchanged with or replaced by
COMBUSTIOY PlPE ASSEMBLY
I
VALVES
CHECK
PIPE EXTENSION VALVE
FRE
H I G H V A C U U M SIGNAL
\
"y
E E l N C SUPPLIED T O
Id
DIVERTER VALVE
I N CLOSED POSITION AIR PUMP
AIR PUMP
DUMPED 1
'PUT
,TMO 'SPHERE
J
Fig. 60-2 1 Schematic of A.I.R. System
a carburetor or distributor designed for engines without
the A.I.R. System.
The air injection pump (Fig. 6D-22) with an integral filter,
compresses the air and injects it through hoses into a
passage in the cylinder heads and into the exhaust system
in the area of the exhaust valves. The fresh air helps burn
the unburned portion of the exhaust gases in the exhawt
system, thus minimizing exhaust contaminations.
The diverter valve (Fig. 6D-23) when triggered by a sharp
increase in manifold vacuum, shuts off the injected air to
the exhaust port areas and prevents backfiring during this
richer period.
-
REAR COVER
\
HOUSING
FILTER FAN-
/ - \
VENT HOLE
I D 0 N O T OIL]
/
\
DRIVE HUB ROTOR SHAFT
Fig. 60-22 Air Injection Pump