Erratic Timing on Timing Light

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Dec 22, 2002 | 06:36 PM

Langadorf

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From: La Jolla California

Erratic Timing on Timing Light

I've previously used this adjustable timing light w/ my MSD 6AL before and it seemed to work fine. Tonight, I was trying to tune my timing, but it seems to jump all over the place and not respond to me moving the ****. Could this timing light only intermittantly work w/ my MSD or is something else going on? See my sig for my engine specs.

Thanks

Dec 22, 2002 | 07:09 PM

fauxrs

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From: San Diego CA

Re: Erratic Timing on Timing Light (Langadorf)

Quote:

Yes, your timing light could be bad, you could also have a stretched timing chain. If you are not having any problems with idle or power then it is most likely the former. See if you can borrow a timing light from a friend and check it with that.

Dec 22, 2002 | 07:18 PM

1979toy

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From: Wichita, KS

Re: Erratic Timing on Timing Light (Langadorf)

1. Borrow a timing light from a friend.

2. Check your harmonic balancer for slipping.

3. Check the advance unit in the distributor.

4. Check the timing chain.

I hope it's one, two or three. Good luck.

Dec 22, 2002 | 08:27 PM

Langadorf

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From: La Jolla California

Re: Erratic Timing on Timing Light (1979toy)

How would I check the timing chain for stretching (besides pulling the timing cover)? What would symptoms of a stretched timing chain be? It seems to idle evenly and acellerate just fine (although I haven't REALLY gotten on it). I just put new heads on it and have been tweaking idle/timing etc. trying to get it up and running optimally.

Dec 22, 2002 | 09:30 PM

Les

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From: Sierra Foothills CA

Re: Erratic Timing on Timing Light (Langadorf)

If your timing light has the type of connector that clamps onto the plug wire make sure it has no cracks in the plastic, and also that it isn't leaning against another plug wire- either of these can cause it to pick up spark from another wire besides the #1 and cause the problem you're experiencing.

Dec 22, 2002 | 09:50 PM

LAvetteman

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From: South Central Louisiana

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Re: Erratic Timing on Timing Light (Langadorf)

I am in the same boat as you. My timing was allover the place last time I had a light on it, which was a non-adjustable light. Since, my MSD has craped out and is being repaired. I'll let you know what happens when I get it back and in, I'll have a band new adjustable timing light then also.

Dec 22, 2002 | 10:28 PM

Jim Shea

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From: Saginaw Michigan

Re: Erratic Timing on Timing Light (Langadorf)

If you have the type where you clamp around the #1 plug wire, you might also simply try reversing the clamp on the wire. Just detach it and turn the clamp over and reattach.

Merry Christmas,

Dec 23, 2002 | 01:05 AM

Kevin_73

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From: Standing still with all my might Texas

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Re: Erratic Timing on Timing Light (Langadorf)

Quote:

I found out that my timing chain was stretched while I was adjusting my valves. When I was manually turning the crank to set it at TDC I noticed that the open valves did not beging moving immediately when I changed the direction of rotation :eek: . Mine would go almost 10 degrees before the cam caught up with the crank :D :D :D :D .
I sure am glad that Bubba "rebuilt" this engine before I bought the car from him :rolleyes: :lol: .

You should be able to simply remove a valve cover and manually rotate the crankshaft a few degrees (10-15) either direction while watching the valve train, if you see some dead space (i.e. valve train not moving) after changing the direction of rotation, then you could probably use a new timing set. Hope this helps.