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----Is my Jeep running 180 degrees out of phase???

1373 Views 3 Replies 2 Participants Last post by  pnut
Orange from Distributor = minus (-)??????? Is this right?
Purple from disttributor = plus (+)?????? Is this right?

1982 CJ7 with MSD, stock dist, MSD coil, Howell TBI.

I just rewired my Jeep custom (Nov to now). Before the rewire it ran perfect. Now I started it and it "runs" horrible for few seconds only. I get spark, and I have confirmed the fuel pump is OK. However when I do get it to "start" is runs rough, and backfires though the carb. It almost sounds VERY lean. I THINK it may be running 180 degrees out.

So to make 100% sure I need to know the polarity of the distributor wires

If I had the distributor wires switched, would my engine run 180 out, and cause the symptoms I describe? Could I have caused any damage?? (It made a horrible crunch noise after the 3rd time I tried to start it)

If I had the coil hooked up wrong, or a mixed TFI wire, would that cause such a problem?

Thanks guys, need your help here to make sure.
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Re: ----Is my Jeep running 180 degrees out of phas

Reversing the orange and purple wires will not cause the timing to be 180 out, impossible.
And, it's not possible for the engine to run when timing's 180 out either. After one cylinder fires, the intake valve would open letting fire burn all the fuel in the intake. Backfires only, cannot run 180 out despite rumors. Try it!

But reversing those orange and purple wires will cause the module to trigger wrong, timing will be a little retarded if you haven't touched the distributor.
The pickup coil puts out 2 pulses for each little wing on the shaft - one from each flat part of each wing - through the orange and purple wires. The first pulse is when the wing gets close to the coil, the pulse goes up, then down. Then as the wing gets passed the coil, it makes another pulse, this time the opposite polarity from the first one.
When you reverse those wires, the module triggers on the second pulse, rather than the first one. The first one is sharper and works better.
If you aren't sure if you reversed them, swap them. Your timing MAY have to be adjusted two or three degrees or so, but no big deal.

Check the black wire where it goes into the distributor, then to a tang - make sure the screw on that tang inside the dist by the feed thru is a good connection. They corrode, that's the ground for the entire ignition system, so it's important.
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