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I just replaced my tank and fuel lines and I went to start my car up, no power. No surprise, it has been sitting for a few weeks. I figured I would just replace the battery since the one in there was pretty old anyway. So, I hook up the negative terminal on the new battery and as soon as I touch the positive terminal with the connector, disaster strikes. Lots of smoke comes from the connecting wires(The ones that connect the battery). Dam! So I take out that battery, put in the old one and try to jump it. As soon as I hook ground the last jumper cable to the engine block more smoke comes from the wires and the jumper cable clamp connected to the engine block turns red hot. Also I think I saw a few sparks from the alternator. I let it cool down and try to jump it again and nothing happens whatsoever. So, I figure I have just fried the hell out of something, but I don't know what. Also, I'm not sure the old battery was actually dead. When I hook up the cables to it and touch the other two ends together, sparks fly. Any ideas what I have just ruined and how it can be fixed? I know nothing about electrical stuff.
 

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Sounds like the positive is grounding out on something. Trace it to find out where... I had a similar problem with a POS Camaro many years ago.

Stan
 

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AKA Exchevman
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Just a word for the wise, use safty glasses at the least when working around the battery. I've seen them blow up, not a pretty sight, or lack of, with acid in your eyes. :: :( A dead short can blow them )
 

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NEVER (let me say that again) NEVER keep trying to hook up a car that exhibits that behavior!!!!!


Take the alternator to a store that tests them.....first guess is the alternator diodes are gone.
 

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Current cars include 1969 Mach 1 and 1970 Cougar XR7 convertible
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Small point...I was taught to hook up the positive battery cable to the positive battery post first, and then the negative to the negative. Are you sure you're hooking positive to positive and negative to negative??
 

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Always hook the positive battery cable up first and unhook the negative cable first!

I had kind of a similar situation recently. I bought a '68 that had sat partially disassembled for 20+ years. Pulled the motor and replaced it with another 302, but I reused things like the alternator and power steering pump, etc. The first time we hooked up the battery, we got a medium-sized spark when the negative battery cable touched the terminal, but no smoking or continued weirdness, so I fired it up--DOOFUS!

I was all excited and wanted to let it run for a few minutes, then trace the wiring later and look for the short--no big surprised to have a problem after 23 years, right? It ran and everything *seemed* ok, but when I went looking for the short, it was in the little wiring harness on the alternator; I could see melted plastic and burned wires.

To make a long story short, it turns out that the alternator must've been from another old Ford (C9 part number on it--I didn't look closely when I installed it--more Duffusy behavior) and was tossed in with the '68 misc. parts sometime over the years. Even tho the harness plugs were the same, the wire configuration was wrong. LUCKILY, it only fried that little piece of my harness--I cringe to think about what could've happened to much more of my wiring had I contiuned trying to run the car with that situation.
 
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