Specifically:
* Harmonic Balancer: Look for a series of marks on the outer edge of the harmonic balancer. These marks are usually etched or stamped into the metal. One mark will be a reference mark (often a notch or a line), and there will be other marks representing degrees of crankshaft rotation. The location of these marks can vary slightly depending on the engine (e.g., a 6-cylinder versus a V8 will have different markings).
* Timing Chain Cover (or Timing Gear Cover): A corresponding mark is located on the timing chain cover (if it's a chain-driven engine) or the timing gear cover (if it's gear-driven) directly aligned with the balancer markings when the engine is at top dead center (TDC) on the number one cylinder. This mark helps you verify alignment during timing adjustment.
To find them: You'll need to remove the shroud covering the timing components to clearly see the balancer and the marks on the timing cover. A shop manual specific to your 1973 Chevy Nova's engine (6-cylinder or V8) will give you the most precise location and interpretation of these marks. Always consult the correct manual for your specific engine.
