Location of Timing Marks:
* Harmonic Balancer: Look for a notch or mark on the outer edge of the harmonic balancer. This mark should align with a corresponding mark on the timing cover. The balancer mark is usually a single notch or a small line. The balancer is the large pulley at the front of the crankshaft.
* Timing Cover: The timing cover (the metal cover over the timing gears) will have a mark or marks indicating the Top Dead Center (TDC) for the #1 cylinder. This is crucial. You’ll need to find the TDC mark; it will usually be a pointer or a line cast into the timing cover, aligned with the appropriate balancer mark.
Finding TDC (Top Dead Center):
Because you're working with the timing, accurate TDC is critical. Don't just rely on the marks. It's strongly recommended to verify TDC using a piston stop or by turning the engine very slowly by hand and checking with a piston stop (a tool that fits into the spark plug hole to physically confirm piston position) to confirm that the #1 piston is at the absolute top of its stroke.
Important Note: The exact location and appearance of these marks can vary slightly depending on the specific engine variant. A shop manual specific to your 1987 Camaro 305 TBI is highly recommended to ensure accuracy and avoid damaging your engine. These manuals provide detailed diagrams and instructions.
Without a shop manual, attempting timing adjustment on an engine is risky. Incorrect timing can cause significant damage.
