Ford Pick-Ups/Bronco 1976-1986 Repair Guide

Ignition Timing Adjustment


See Figures 1, 2, 3, and 4

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Fig. Fig. 1: Timing marks for the inline and V6 engines

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Fig. Fig. 2: V8 timing marks

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Fig. Fig. 3: Using a timing light

With the Dura Spark II system, only an initial timing adjustment is possible. Ignition timing is not considered to be a part of tune-up or routine maintenance.

With the TFI-IV system no ignition timing adjustment is possible and none should be attempted.


  1. Locate the timing marks on the crankshaft pulley and the front of the engine.
  3. Clean the timing marks so that you can see them.
  5. Mark the timing marks with a piece of chalk or with paint. Color the mark on the scale that will indicate the correct timing when it is aligned with the mark on the pulley or the pointer. It is also helpful to mark the notch in the pulley or the tip of the pointer with a small dab of color.
  7. Attach a tachometer to the engine.
  9. Attach a timing light according to the manufacturer's instructions. If the timing light has three wires, one is attached to the No. 1 spark plug with an adapter. The other wires are connected to the battery. The red wire goes to the positive side of the battery and the black wire is connected to the negative terminal of the battery.
  11. Disconnect the vacuum line to the distributor at the distributor and plug the vacuum line. A golf tee does a fine job.
  13. Check to make sure that all of the wires clear the fan and then start the engine.
  15. Adjust the idle to the correct setting.
  17. Aim the timing light at the timing marks. if the marks that you put on the flywheel or pulley and the engine are aligned with the light flashes, the timing is correct. Turn off the engine and remove the tachometer and the timing light. If the mark are not in alignment, replace the ignition module.

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Fig. Fig. 4: Underhood emissions sticker