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FlMudCJ\'s Questions....

*FlMudCJ* asked,
*Is it bad when the terminals inside the distributor are burned???? I don't really see any traces of cross firing, but there are two distinct spots on each contact that look like its where the spark is jumping from rotor to terminal... Its a '77 prestolite system...*

This may be a problem. It looks like you are getting one of the burn spots when the engine is an rest, (no advance), and the second at full advance.
The two burn spots are probably pretty close to the edges of the terminals if this it.
It means your centrifugal advance, or vacuum advance, or both are malfunctioning.
Prestolite is famous for it's 'Now it works, now it don't' advance mechanisms...

To TEST...
1. Pull the vacuum line off of the distributor and plug it. Hook up a timing light and get ready.
2. Start the engine, and rev it up with the timing light on the balancer. If the timing goes up (advances) at a nice even pace as the rpm goes up, the centrifugal advance is probably working all right.
3. Continue watching the balancer at idle, and hook the vacuum line up to manifold vacuum. At idle, vacuum should be high, and immediately advance the timing. If it goes up smoothly but quickly, it's probably working. Remember to hook up the vacuum line to ported vacuum.
4. Cut a hole in an old distributor cap, and shine the timing light in the cap so you can see what's going on. This clears up a lot of 'Whys' and 'Whats'.

If this doesn't find it, I'm stumped...
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*FlMudCJ* asked,
*I found the screw hole in the distributor housing you mentioned... Is it ok there isn't anything screwed in? should I seal it when I assemble it on the jeep?*

I'm answering a question of yours above, and you said you have a Prestolite...
The screw hole should only be in a Motorcraft distributor.....
Now I'm confused.....

If you have changed to a Motorcraft, the screw hole should have a screw in it holding the cap locating tab in place...
If you have a Motorcraft distributor, buy or make a locating tab, and secure it to the distributor housing with a screw via this hole.

If you have a Prestojunk distributor, I have no idea what that hole is supposed to be for...

Later dude, Good luck, Aaron.

If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?
 
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Re: FlMudCJ\'s Questions....

WOW, my own thread... ;)

The burned cap is in my prestolite distributor... I'm ditching the whole thing and doing the motorcraft upgrade. That said, I was wondering if the cause and effect of these weird marks in the cap were totally limited to the distributor...

I was wondering if I directly replaced the prestolite system with motorcraft that I might be dragging another problem into the motorcraft system. However, with this answer, I'm going to assume that the upgrade will still be a yank and plug affair.

The question of the tapped hole was for the motorcraft distributor. How important is the locating tab, so long as I know that the cap base is to be lined up with the hole?

I think that's it for now... /wwwthreads_images/icons/crazy.gif

I don't know why I'm even bothering, the jeep is imobile until like... april the way things are going... :p

But thanks, I'm printing them out for later refrence... If that's ok...

Florida Mud CJ-5
'77 RB304, t-150 D20 4" 35" swampers
 
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