IGNITION TIMING

Durant, all Models 1928-29 (semi-automatic spark advance)

To time the spark to the motor, crank the engine until No. I piston is approaching T.D.C. of the compression stroke and the "IGN" mark on the flywheel mark D.C, 1-4 or 1-6 registers with the indicator in the flywheel housing. On models not equipped with au enclosed flywheel, the indication for piston position is the center line of the casting of No. 4 or No. 6 cylinder with the spark control in the full advance position.

The distributor should be set so that the points are fully open and the rubbing block of the breaker arm is on the leading edge of the cam peak. When in this position the rotor should be under the terminal leading to No. 1 spark plug. Due to the slight variation in the action of the automatic advance mechanism, it may vary from the Ignition Timing Table.

The following table contains complete ignition timing specifications for Durant automobiles. Complete details for tuning procedure will be found in this section under the car model heading.

IGNITION TIMING TABLE

Year Model Con.C Pt.Fly Dead Spark Plug Gap Firing Order
1928 M-4 .020" 4 teeth B.T.D.C. Adv. .027" 1-3-4-2
1928 55 .022" 0* T.D.C. Ret. .027" 1-5-3-6-2-4
1928 65 .022" 0* T.D.C. Ret. .027" 1-5-3-6-2-4
1928 75 .022" 2 teeth B.T.D.C. Adv. .027" 1-5-3-6-2-4
1929 440 .022" 4 teeth B.T.D.C. Adv. .027" 1-2-4-3
1929 60 .022" 2 teeth B.T.D.C. Adv. .027" 1-5-3-6-2-4
1929 66 .022" 2 teeth B.T.D.C. Adv. .027" 1-5-3-6-2-4
1930 6-14 .022" '6' B.T.D.C. Adv. .027" 1-5-3-6-2-4
1930 6-17 .022" '8' B.T.D.C. Adv. .027" 1-5-3-6-2-4
1930 407 .022" '6' B.T.D.C. Adv. .027" 1-3-4-2
*Flywheel is marked for ignition timing

If it be found necessary to alter the ignition timing from that described above. On some distributors best performance is obtained when the points are set to just break contact while others require the rubbing block of the arm to be set at the peak of the cam. Road testing the car will determine the setting best suited to the motor. (See ignition-timing table).

Durant, Model 6-14, 6-17 and 407 1930--To time the spark to the motor, crank the engine until No. I piston is approaching T.D.C. of the compression stroke and the "IGN' mark on the flywheel registers with the indicator of the peephole in the flywheel housing with the spark control in the full advanced position. The distributor should be set so that the points just break contact with the rotor under the terminal leading to No. 1 spark plug. (See ignition-timing table).

Information Donated by Carol Rush