Incorrect Ignition Timing Consequences?

PostPost by: William2 » Sat Nov 02, 2019 4:48 pm

If you try and start an engine and the timing is out is there any danger of damaging it or will it just refuse to run or run badly?
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PostPost by: Donels » Sat Nov 02, 2019 5:35 pm

I presume you are talking ignition timing and not cam timing? It really does depend on how far out the ignition timing is. +/- 2 - 3 degrees and it will run ok. More advanced and it will eventually overheat the pistons, more retarded and the exhaust will start glowing. +/- some more and it won?t start or run. I think you need to be more descriptive with your problem to get real help.
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PostPost by: William2 » Sat Nov 02, 2019 5:56 pm

Sorry for my poor description. The situation is that I have had the cam shafts out to re-shim some of the valve clearances and in spite of keeping a constant tension on the timing chain, there is a possibility it moved during the process. The cam timing is certainly correctly reset.
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PostPost by: Donels » Sat Nov 02, 2019 6:14 pm

So the issue is that the distributor cam drive may have slipped a tooth?
If so just reset the timing. If the dizzy is pointing wrong, set the crank notch to the timing mark and the lift the dizzy to where you want it, then retime.
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PostPost by: nmauduit » Sat Nov 02, 2019 6:22 pm

it is almost certain that the spark timing will be off when adjusting valve shims. I had been told that, yet tried a number of tricks, and came to the same conclusion : best to just retime properly the dizzy after the shiming is done.

as to your question, just trying to run the engine statically with the timing off will not damage it (but running the car under load on the road for extended period with a timing off may lead to different situation, depending on actual situation).
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