You'll need to look at the front of the engine, specifically the harmonic balancer (the pulley at the very front of the crankshaft). The timing mark is usually a small notch or line cast into the balancer itself.
To find it:
1. Clean the area: Thoroughly clean the front of the engine, especially the harmonic balancer, so you can clearly see the markings. Grease and grime can obscure the mark.
2. Locate the timing pointer: There's a pointer or indicator, usually part of the timing cover or a separate pointer, that lines up with the timing mark on the balancer.
3. Find the mark: The mark on the balancer will usually align with the pointer when the engine is at Top Dead Center (TDC) on the #1 cylinder's compression stroke. Your owner's manual or a repair manual specific to your year and engine will have diagrams and instructions on how to ensure #1 is at TDC.
Important Note: There might be multiple marks on the harmonic balancer. The correct mark is crucial. Using the wrong mark will result in improper timing, potentially causing damage to your engine. Refer to your repair manual for the specific mark to use for your engine. A Haynes or Chilton manual for your Bronco should be extremely helpful here. Without the correct manual, you run a significant risk of setting the timing incorrectly.
