Datsun Roadster Forum-311s.org

So - car has been in parts for 9 months. New Battery - with reversed orientation of the positive and negative. Hooked it all up and...

- smoke filled the Amp gauge
- harness connected to the front wiring harness smoked
- connector around the generator smoked

So... wisdom of the boards, pray tell what damage have I done and I need to look at in the morning...

The power was not on for long 15-20 seconds, fear another harness has done and possibly the ammeter which I know is as rare as heads teeth....

Suggestions and condolences welcomed.

Oh my, 15-20 seconds is enough to heat up the ammeter wire and melt it and the wires next to it. Check it carefully before you hook it up again.

65 1600 is positive ground?

Look how little time this takes.

@curtis



Lets see which harness I need to replace next....

Ugh... so sorry man. I shorted my alt on the street once and was fortunate that it only cost me the amp gauge.

@Gregs672000

The Amp Gauge is toast - just taking the dash apart this morning to see if I need a new Dash harness as well... fortunately, when re-powder coasted the dash, I had to run a earth cable from each of the instruments to the body. That melted super quickly, so it *may* have saved me....

Just when I thought I was going to get it back on the road this weekend....

A good little trick I always use any time you are worried that you may have a potential short situation,
hook the earth side of battery up as normal, but on the positive side just wind a piece of fuse wire round the connector and run a few inches out
and wind 3 turns around the battery post, then when you turn on the ignition any problem will just blow the fuse wire, if all good connect up the positive terminal...

That is a great suggestion! And one that would have saved the Ametwr and several wire harnesses!

Bummer . I feel your pain .. hang in . It'll turn out better than it was now . Spring has not hit yet ..

My buddy did the same to his 67 and then sold it to me a few years later. My ammeter was toast but the harness survived. However, my fuel gauge and temperature gauge have not worked. I have built my own voltage regulator, but they still didn't work. Am in the process of installing another voltage regulator from a donar car. Is there any way that the reversal of the battery cable may have fried those wires only?(fuel&temp)

I toasted the ammeter. Other gauges seem to be just fine.