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Polarity Conversion Issues?

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J

jbmcohen

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Hello -

The prior owner of my BJ8 switched the wires on the sports coil, which I believe affects the polarity to negative ground? I recently switched the wires back. Now the car occasionally stalls while I'm driving, which it didn't do before. If I catch it fast enough, I pump the gas pedal and that usually alleviates the occurance.

Otherwise, the car will start back up, usually on the first try.

Any idea what this can be from?

Thanks for the help!
 
When you went back to pos ground, did you re-re-polarize the generator? Actually, a better question is did he (previous owner) completely convert the car to Neg ground, or did he just switch the coil wire? And how much converting did you do?
 
Greg -

I believe he just switched the wires on the coil. What's involved in the re-re-polarizing of the generator? I switched the tachometer's wiring back (that you helped me with). That's all so far? Anything else to look out for?

Thanks again.

Barry
 
The coil will work with the wires set either way, but one way will give you a better spark, is usually marked + - or SW CB on the two leads from the coil, my first guess is when switching around the wires you went to the way that gives a weaker spark, if you don't have it pick up or download a copy of the Lucas Electric Fault finding manual tells you how to test I beleive, you can download it on John Sims Healey 6 website, which is a great resource.

Greg
 
Well, if you're going completely back to positive ground, there are a couple things. The cables to the battery need to be switched, the battery terminal marked "-" should have the cable that goes through the bulkhead of the trunk. The positive terminal would go to the frame via the cut-off switch (if you still have that connected). The fuel pump might be sensitive to polarity. #2 HERE shows you how to polarize the generator. Just remember if you're switching to positive, the hot lead would be negative polarity. You've already done the tach and coil, so that should be it.
 
Where is the neg pole of the battery connected? If only the coil is switched, that does not mean you have neg ground (earth). Figure that out before you do anything.
 
If you are still pushing postive ground, the spark goes in the wrong direction if the coil wires were switch. Car will still run but with a weaker spark. Go with the way it should be and look elsewhere for the engine quitting.
 
Distributor is ground,always, whether it be Pos or Neg grounded vehicle. Reversing leads on coil can & usually will cause points to burn& sometmes condensers to fail. cheers Genos2
 
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