Quote:
Originally Posted by Flygirl
What would I see, if anything, on the plugs if max advance or the timing curve is improperly set? Would there be physical damage that was apparent...? Or is it more of a color shift?
|
If you have decent vision, you can "read" a spark plug and tell if the timing is in the right spot.
First of all, I will say that if timing is way off, you can damage the engine and you will probably start to see flecks of aluminum (from the piston) on the spark plug itself.
Other than that, there is a "band" that you will be able to see on the ground strap of the plug. The strap has a 90° bend on it. If the timing is pretty spot on, you will see a "band" right in the apex of that bend. Different amounts of timing will move that band back and forth on the strap. Too much timing will push it towards the threads, not enough will push it towards the tip of the electrode. This all has to do with heat transfer.
So by reading a plug, you can tell if an engine is running rich, lean, if it has a blow-by issue, and you can also tell how close you are on ignition timing.
I forgot to add....
You can see where you are on the heat range by looking at the last few threads of the plug. You want a couple of threads on the plug to show signs of heat.