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Old 02-21-2012, 07:05 AM
lt1silverhawk's Avatar
lt1silverhawk lt1silverhawk is offline
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Hey cobalt,
Originally Posted by cobalt327
I wasn't able to see the video (problem on my end), does the choke ever completely open?
When the truck is first started, the choke pull off starts working immediately, and the choke plate opens up to the 3/4 of the way before coming back up to about half way open a few moments later. However, I can't seem to tell if the choke it self is working (divorced choke). Perhaps if any of the other members can tell, they can chime in.

Originally Posted by cobalt327
The timing mark won't be visible if the vacuum advance is hooked up to a manifold vacuum source,

If it was disconnected and plugged, the timing tab/damper line may be off; there were three Gen I tabs/dampers that may be confusing the issue.
The vacuum advance is hooked up on the carburetor. I'm not sure if that could still be manifold vacuum though. I did not disconnect or plug the advance while trying to get an initial timing reading. I will check up on the tab and damper to make sure everything is good there. The timing tape looks like an interesting project to make.

Originally Posted by cobalt327
DETERMINING TDC will allow you to be sure the timing tab and damper are correctly indicating TDC.

MAKE A TIMING TAPE to see what the total timing is, w/o needing to use a dial back timing light. You can also buy a timing tape, get one that matches the diameter of your damper.

The image shows the correct orientation of the timing tape:
I did remove and reinstall the distributor several times last year and "found" the TDC by using the timing tab. It was last set at 9 degrees BTDC on the damper (see pages 10 through 13 for reference on that). If need be, I can do so again after making sure the timing tab and damper are ok.

Originally Posted by cobalt327
Because the distributor is running the engine, I doubt the drop did any real harm. I would expect a no-start condition if the module or pick up coil had been damaged by it falling. Sometimes modules will run fine cold but give problems when they're hot. The pick up coil can exhibit erratic behavior if the wire inside the insulation is broken from the movement of the advance plate on the distributor.
Yes, there have been no issues with starting. The coil itself was recently replaced a couple of weeks ago. And module "passed" the test at Autozone a few times. If the temperature can be an issue for the module, I think I ran the truck long enough to get it warmed up enough and would have noticed if there were any issues. But I suppose it could be random if the module acts up or not?

Originally Posted by cobalt327
If you need it:


HERE'S an exploded view of an HEI distributor.
THIS is a description of an HEI rebuild. HERE is another HEI info/rebuild page.
Thanks! If it comes down to it, I can take it apart and check everything out. Now I have a better of idea how of the insides work.

Thanks for the continued help!

Last edited by lt1silverhawk; 02-21-2012 at 07:13 AM.
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