Timing problem on 55

[Fenwick B.]

I am still chasing a small problem with my 55 running rough. I now think that it may me a timing problem. I am using a timing light with a dial on it, so I can turn the dial to get the flash on the mark, but the flash does not stay in one place all of the time. I appears to be moving about 20 degrees. What can be causing this?
Fenwick Binder

[Larry M.]

Re: Timing problem on 55

Fenwick:

I think that you need to borrow another timing light. It sounds like something in the timing light electronics is failing.

A few years ago, I purchased a new Sears (Actron) dial-back timing light. It worked perfectly, and the timing advance agreed with my old, standard timing light. I stored the new timing light in the garage. The following year I tried to use it, and it behaved erratically like you described. I replaced it with a new Sears dial-back light. It appears that something either failed in the dial-back electronics or that the excessively high humidity in our (New Orleans) area affected the dial-back rheostat. I now keep the new timing light in the air conditioned house in a desk drawer. No more problems.

It seems that every month, some new corrosion-related electrical problem crops up with my 1967 Corvette. Old Corvettes and New Orleans humidity do not go well together.

I would also check whether the vacuum advance can could be causing the erratic timing. Be sure it is disconnected when you make your checks. Then re-connect and see what happens.

I'll try to come up with some other or better ideas later, if the problem persists. Good luck.

Larry

[Stuart F.]

Re: Timing problem on 55

We have the same high heat & humidity here in Orlando. My 63 has deteriorated more in 4 years here than all it's previous life in Wisconsin and Illinois. The winters weren't so bad for it afterall. I'm trying to compensate for the problem as fast as I can with Garage improvements, etc., But it seems I can't act fast enough.

Stu Fox

Is the 55 a 6 or an 8?