1. Verify Piston is at TDC on the Compression Stroke:
* Rotate the engine by hand: Using a wrench on the crankshaft bolt, slowly rotate the engine clockwise (as viewed from the front of the engine).
* Check the timing marks: Locate the timing marks on the crankshaft damper (harmonic balancer) and the timing tab on the engine block. These should align when piston #1 is at TDC on the compression stroke. This is crucial – getting it wrong will result in the distributor being 180 degrees out.
* Check the #1 piston: If you have access to the #1 spark plug hole, use a piston stop or a long, thin rod to ensure the piston is actually at its highest point. It will be moving *up* when you reach TDC on the compression stroke. If the piston is moving *down*, you're on the exhaust stroke - keep rotating until it's moving up again.
2. Locate the Rotor's Position:
* Distributor gear mesh: Ensure the distributor gear is properly meshed with the camshaft gear.
* Rotor position: With piston #1 at TDC on the compression stroke, the rotor should point towards the #1 spark plug wire terminal on the distributor cap. If it doesn't, the distributor is likely 180 degrees out.
3. Installing/Adjusting the Distributor:
* Lightly lubricate the distributor gear: Use a little engine oil on the distributor gear before installing.
* Insert the distributor: Carefully lower the distributor into place, making sure the gear meshes smoothly with the camshaft gear.
* Initial alignment: You may need to rotate the distributor slightly to align the rotor with the #1 terminal. There's typically a small amount of play.
* Tighten the distributor hold-down clamp: Secure the distributor in place once the rotor is roughly pointed toward the #1 terminal.
4. Fine-tuning (Optional but Recommended):
* Using a timing light: This is the most accurate method. Connect the timing light to the #1 spark plug wire and the battery. Crank the engine. Observe the timing mark on the crankshaft damper. It should be approximately at 0 degrees before TDC (BTDC) for a stock engine. Consult your engine's specifications for the precise timing. Adjust the distributor slightly to achieve the correct timing if necessary.
Important Considerations:
* Engine Rotation: Ensure you are turning the engine in the correct direction (clockwise as viewed from the front).
* Accuracy: It's crucial to be precise during this procedure. An improperly aligned distributor will result in poor engine performance, misfires, and potentially damage.
* Reference Materials: Consult a reliable repair manual specific to your 350 Chevy engine for detailed diagrams and specific timing specifications. The year and model can significantly impact details.
* Safety: Always disconnect the negative battery terminal before working on the ignition system.
If you are uncomfortable performing this task, it is strongly recommended to seek the help of a qualified mechanic. Incorrect distributor alignment can cause significant engine problems.
