Ignition Timing: Adjustments

Timing Marks:

Fig. 1 Distributor And Hold Down Screw:

1. Set the parking brake and insure that the transmission is in PARK Or NEUTRAL. Turn all lights and accessories OFF.
2. If using a magnetic timing unit, insert the pickup probe into the receptacle next to the upper, left bell housing bolt on the transmission. If you will be using a conventional timing light, connect the ignition pickup on the number one cylinder spark plug cable.
3. START the engine and allow to idle for five to ten minutes or until it is at operating temperature.
4. Adjust engine idle, if necessary, to the specifications on the EAR label in the engine compartment.
5. Disconnect the 6-way connector on the carburetor, remove the purple wire and reconnect the connector. START the engine and raise engine speed to 1200 RPM and release.
6. Remove and plug the hose at the vacuum transducer and recheck idle RPM.
7. If using a timing light, check ignition timing at the timing marks. If using a magnetic timing unit, check the meter reading. Reinstall the vacuum hose at the vacuum transducer and remove all test equipment if timing is within 2° of the value specified on the EAR Label. If the basic timing is not correct, proceed to step 8.
8. Loosen the distributor hold-down bolt, allowing the distributor to be turned with some resistance, and adjust the basic timing to the specifications on the EAR label. After adjusting the basic ignition timing, recheck the idle RPM and secure the distributor. Recheck the timing once again to verify that the timing is correct.
9. Turn OFF engine and reconnect the purple wire of the carburetor 6-way connector.
10. Reinstall the vacuum hose at the vacuum transducer and check the curb idle RPM and adjust as necessary. Disconnect all test equipment.