How to Set the Ignition Timing on an Engine

Setting the ignition timing on an engine is one of the most crucial parts of engine repair. Without proper timing, the engine will never run.

Difficulty: Moderately Challenging

Instructions

1. First, identify the number one cylinder on the engine, this can be found in your owners manual. You will also need to know the firing order for the engine, for example, on a 4 cylinder tractor engine, it is usually 1-3-4-2. Once you have this established, go to step 2 and get started.

2. First, have the spark plug wires connected to the plugs, but not the distributor cap. Remove the distributor cap, but leave the rotor in place. Set the engine so that the number one piston is at Top Dead Center of its COMPRESSION stroke, this can usually be identified by either a mark on the flywheel or, with both valves closed, set the piston at TDC.

3. Now, the rotor will be pointing at the number one terminal on the distributor cap, this is where the wire from the number one spark plug goes, then, following the firing order, go around the distributor cap in a clock wise direction, or, check the direction of rotation of the rotor. For example, with a firing order of 1-3-4-2, with clockwise rotation of rotor, you found the number one terminal, next terminal would be wire 3, then 4, then 2.

Tips & Warnings

• For fine tuning of the spark timing, there will usually be a small clamping screw at the base of the distributor that can be loosened, the distributor can the be turned slightly in either direction to advance or retard the spark timing.
• Never attempt this with the engine running!

[withmore]

on 12/3/2009 very great detailed article, thanks