Electrical death!

[jon1fox]

My 1973 240Z is dead. It was Thanksgiving and I was on the freeway driving to work and it started to die. Then it backfired for the first time and kept going. About 15-20 seconds later it died again. No power, nothing. When I pulled over I noticed my amp/fuel gauge was smoking. After I had it towed I pulled the gauge out. It was blown. The lead wire coming off of the starter that goes through the firewall is fried as well. I replaced the wire and bypassed the amp gauge to see if I could get the car to start. Nope, just more fried wires. I didn't notice any bad connections to the alternator. What could be causing this? I'm this close to tearing everything out and redoing the wiring. I just don't want to redo the wiring and have this happen again right after. Any thoughts?

[240ZX]

Well jon1fox,

Sounds like the old corrosion monster has finally overwhelmed your electrical system. This is a common thing with the older Z's. The basic problem is that corrosion has gotten so bad especially the connectors, that it creates high resistance in the circuits and like yours has gotten so bad that the wiring can no longer handle the current and then a wire fries. So, now you will likely become very familiar with the electrical system on an early Z, if you choose to tackle the problem yourself. So you want to ask yourself.....do I have the skills, knowledge, and tools required to do the task? If you do, you already know what's ahead. If you don't feel confident in doing it yourself, take it to someone who is very familiar with these systems. It is time consuming to trouble shoot and will cost you some $$$. Sorry to hear about your Z but there are no easy answers to pin point your problem, in my opinion. Hopefully, some of the guys here will pitch in with some additional advise. Good luck!

[Daniel]

The obvious reason for the melt down is a short/and or poor connection. The location of course is the issue. First keep in mind one of those wires from the starter was a fuseable link. It should not be replaced with any thing but that. My first area of inspection would be the harness under the battery. Years of acid drip may have taken their toll.Just because the tape may look good,who knows what someone did once upon a time. Next would be to start an inspection of connectors. That hot should be very visable. If not undo them one a time till you find it. Odds favor the trouble being where hands have touched it . Not in the wire itself. Except for the acid area.

[beandip]

what was mentioned in passing was the fuseable link. Some time in the past it must have been replaced with a solid wire and when a problem ocured it fried the systime . start at the starter and work back.