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Posted by: Eric Taylor Mar 29 2004, 10:14 PM

So after my fuel pump wiring extravaganza, I found I had some how fried the wire from the points. So tonight I replaced the condensor and point's. This was my first time ever setting points, in the past I had just watched. I set them to what I felt was right, wen't to hit the key, it sounded like it was trying, but nothing was happening. I go back, pull the cap, and the wire to the point's is once again charcol, and it smell's like BBQ. This is so bizzar! The only thing I can think of is that when I put in the 73 relay board the wiring was different, so It smoked them. I'm at a total loss. What's going on here?

Posted by: Brad Roberts Mar 29 2004, 10:19 PM

Many people will tell you that the wiring and boards area all the same..

I have burnt 3-4 wiring harness' by switching between early and late relay boards and early/late starter/coil wiring.

I'm betting you have the tach and coil wire swapped right now. Either in the 14 pin connector or at the coil.


B

Posted by: JOHNMAN Mar 29 2004, 10:30 PM

You are attaching your green points wire to the positive side of the ignition coil causing a dead short. That is melting your green points wire.

To test, leave the points wire disconnected and using a volt meter, test the post that you are trying to attach your green points wire to. You do not want the one at +12V with the key on.

The green wire should be attached to the same terminal as the black/purple stripe (tachometer) wire NOT the solid black +12V wire.

The coil is switched by the points and when the points open, the coil energy field collapses and a high voltage spark is created. The points switch the GROUND. +12 volts is constantly fed to the coil when the key is on.

I hope this helps.

Posted by: JOHNMAN Mar 29 2004, 10:34 PM

Man, it takes me WAY too long to type......

Posted by: SirAndy Mar 29 2004, 11:00 PM

actually, when you look closely at the wireing diagrams for pre '73 relay boards and '73 & later relay boards you'll notic that ALL THE RELAYS have pin 85/86 switched !!!

THEY ARE NOT THE SAME!

Andy

Posted by: Brad Roberts Mar 30 2004, 12:58 AM

Larson.. Bowlsby... I cant think of who else keeps telling me they are all the same.


B

Posted by: Eric Taylor Mar 30 2004, 01:08 AM

Yeah, brad, bet your right. Should I swap the 72 board back in? It's kinda an oxidized piece of crap, but it's worked before. I'll try that tomorrow, and a new set of points. I bet that would explain smoking the insulation off of the tach drive wire. This is starting to make sense. Glad to know the board's are different. At least I have good relay's now! By the way, you guy's are saying that the wire coming off the condensor should go to the neg side of the coil? When I got my car it was wired to the pos. That coud be it too. I'll try relay board's
Eric

Posted by: Brad Roberts Mar 30 2004, 01:10 AM

Flip it back in there Eric and try to locate another 14 pin wiring harness.

THIS TIME check the fat wire for 12 volts to the coil BEFORE hooking it up...


B

Posted by: Eric Taylor Mar 30 2004, 01:11 AM

Brad - Think my harness if screwed? This is the ignition harness. which one's the fat wire?
Eric