Pontiac FIREBIRD 1972 Service Manual page 741

ENGINE TUNE-UP 6C-5
AIR CLEANER ELEMENT
Wash polyurethane element (heavy duty) in solvent and
re-oil with SAE 30 engine oil. Paper element should be
replaced at 24 months or 24,000 miles. Do not attempt to
clean with an air hose.
NOTE: Air cleaner should be serviced after
each occasion of driving under severe dust con-
ditions, and inspected at 12 months, or 12,OIX)
miles.
CHECK FUEL LINES AND SERVICE FUEL
FILTER
1. Inspect fuel lines for kinks, bends or leaks and correct
any defects found. If necessary to replace fuel line,
use copper double flared end lines.
2. Replace filter in carburetor inlet.
NOTE: If a complaint of poor high speed per-
formance exists on the vehicle, fuel pump tests
described in section dB should be performed.
INSPECT AND SERVICE COOLING
SYSTEM
Inspect cooling system for leaks, weak hoses, loose hose
clamps, correct coolant level, and service as required.
NOTE: A cooling system pressure test, as de-
scribed in section 6A may be perfomed to de-
tect internal or external leaks within the cooling
system.
CHECK LUBRICANT LEVEL AND
INSPECT FOR OIL LEAKS
Check level of lubricant in crankcase and inspect engine
for oil leaks.
CHECK CARBURETOR CHOKE AND
UNLOADER OPERATION AND
ADJUSTMENT
The specified choke setting provides ideal choke operation
in all climates. No seasonal changes are necessary. For
setting, see ENGINE FUEL, Section 6B.
CAUTION:
Choke linkage and fast idle cam
must operate freely. Do not lubricate linkage
since this will collect dust and cause sticking.
Check unloader adjustment, see Section 6B.
IDLE STOP SOLENOID
Idle stop solenoids are used on all 6 cylinder engines, as
well as all 4 Bbl. V-8 engines.
See Section 6D for proper idle setting procedures.
CONNECT TUNE-UP EQUIPMENT
Follow manufacturer's recommendations for the use of
testing equipment. Fig. 6C-2 shows a basic schematic for
instrumentation which will apply to many types of test
equipment and may be used as a rough guide if equipment
manufacturer's instructions are not available.
Fig.
6C-2
Schematic of Tune-up Instrumentation
Connections shown in Fig. 6C-2 are made as follows:
1. Timing light
a. Positive lead to positive battery terminal.
b. Negative lead to ground.
c. Trigger lead to number 1 spark plug.
2. Tachometer
a. Positive lead to distributor side of coil.
b. Negative lead to ground.
3. Dwell Meter
a. Positive lead to distributor side of coil.
b. Negative lead to ground.
TEST DWELL AND DWELL VARIATION
Two methods are offered for dwell or point gap adjust-
ment on the vehicle. Whenever possible, a dwell meter
should be used for better accuracy.