Smoking negative

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MustangSally44

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So I was checking the voltage to my fuel tank sending unit and my Daughter was helping by turning the key off and on for me. The next day we were going to go for a ride and the battery was completely dead. Chalked it up to her not knowing to jiggle the ignition before removing the key. Figure the ignition was on all night without the key in it. Part of the charm of an old car , right? I charged the battery to 77% and the motor cranked over great and started. Went to Canadian Tire, Then to Wallmart.. Upon leaving Wallmart, the car wouldn't start . Just a strong click from the solenoid, a bussing from the solenoid area. { solenoid or voltage regulator , not sure which } and a puff of smoke off the negative battery cable at the battery..Called my Daughter for a boost but it didn't work. Put a booster cable from the battery negative to the intake manifold to improve the ground but it still got hot. Came home and got another battery and changed it out in Wallmart parking lot. Still wouldnt start and the cable got hot. This morning I charged the battery to 100% and put a new negative cable on the car taking care to sand the block clean and wire wheel the ground cable bolt. Connections are clean and tight. Tried to start the car but just got a hard click and a hot new negative cable. Sorry for the long winded explanation but i figured i could answer questions before there asked so i wont even go into the $167 tow 4km to my house...oops. Anyway are we looking at a starter or did I fry something else? I was under the impression a bad starter made the positive cable hot. You guys are way smarter at this stuff then me. Thanks in advance.
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Sounds like the starter. The negative cable can get hot if it's shorted out. Disconnect the positive cable from the starter solenoid going to the starter and then see what happens when you turn the key. If the negative still gets hot then you have a short somewhere else.

If you want to check to see if something else is drawing on the battery while the key is off disconnect the positive battery cable and put a 12 test light from the positive terminal to the disconnected battery cable. IF the test light lights, you have a short to ground somewhere. You can start pulling fuses till it goes out. The one that turns the test light off is the bad circuit.

Edited -make sure your doors are closed when you do this. Also, if you have a working clock you will need to disconnect it or any other thing that might normally draw from the battery when the key is off.
 
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so i wont even go into the $167 tow 4km to my house...oops.
What!! No CAA? It's like the credit card ad that says " don't leave home without it"
CAA Premium is what I have and "I don't leave home without it"
I have little electrical knowledge, but it does sound like a serious short somewhere and I'm betting it's the starter, but it all needs to be checked out.
 

Superbond

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If I’m not mistaken there is a fuseable link in that area. And that will stop it from turning over plus there would be smoke when the fuseable wire melts
 
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Does the dome light goes on inside?
If the car was running fine (you cranked and started twice to go to 2 places), I'd make 100% sure the batt is right, then test the starter.
You said you changed the battery for another, if not a new one, are you sure that it has enough cranking juice? Usually after first try these would display 10 or lower volts. Still enough to make your wire get hot if you keep trying.
 

MustangSally44

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What!! No CAA? It's like the credit card ad that says " don't leave home without it"
CAA Premium is what I have and "I don't leave home without it"
I have little electrical knowledge, but it does sound like a serious short somewhere and I'm betting it's the starter, but it all needs to be checked out.
Was racking my brain as to what to get the wife for her birthday....A CAA membership
 

MustangSally44

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Does the dome light goes on inside?
If the car was running fine (you cranked and started twice to go to 2 places), I'd make 100% sure the batt is right, then test the starter.
You said you changed the battery for another, if not a new one, are you sure that it has enough cranking juice? Usually after first try these would display 10 or lower volts. Still enough to make your wire get hot if you keep trying.
dome light comes on when the door opens. Both batteries are good. Wouldn't start with a boost. I'm going to pull the starter off after trying Kilgons suggestions. Just not looking forward to crawling under it in the rain on a gravel driveway.
 
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Did you check the positive cable? The negative cable and positive cable carry the same load, and if it's the starter the positive cable should also be getting hot, assuming both cables are the same gauge.
 
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Sounds like either the starter or the engine has seized. I would pull the starter, it's pretty easy to do and get it tested. Also, try turning the engine by hand (socket on the crank and a breaker bar). It should move pretty easily.
 

Superbond

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You have to try the old school way. When you try to turn it over get someone to hit the starter with a hammer! You never heard that from me🥴
 
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