"Hot" ground wire

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OhioJeremy

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What would cause the ground wire on the battery to get so hot that it literally melted the lead off the terminal. This occurred while cranking the motor over to start after setting a while. Any ideas?
 
First, WHAT are we working on? That question asked........

If that's the only ground, that could do it. Check to see you have grounds from the engine to the firewall. From the engine to the frame rail.

Also, if the starter is drawing to much amperage, that's another possibility.
 
68 barracuda. Just got it in January and finally starting to work on it. Had set for mth or so and decided to start it to move to other garage bay for brake work when it done this. Will check for other grounds. As of now the negative lead Is attached to head.
 
The ground strap from my Honda motor broke and somehow the tach drive cable became a dead short to positive and caught its insulation on fire. Lots of smoke and drama but little damage. Heat is resistance, ie resistance to flow as in a light bulb filament to 12V to ground. A bad connection can cause a hot cable as well as a device drawing mucho amps through an undersized 10G cable like a 1.7kW (at no load!) starter.
 
WHAT engine? It's like pullin teeth.
 
RustyRatRod said:
First, WHAT are we working on? .
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Hot connections/ terminals/ wires come from two sources or a combination of them both

Resistance at some point causes overheating because the effective wire size has been reduced by the bad connection, so to say

High, abnormally high current in a circuit

Or combination of both.

So bad battery clamp connection to post, bad connection to cable, cable corroded internally, and or something causing way too much current. Bad starter, dragging engine, etc.
 
@OhioJeremy, I see you are relatively new, so let me tell you something. When you ask a question about your car, we are HAPPY to help. However, it is very common for people (often newbies) to provide little or no information about the car. Regardless the question, I would provide year, make, model, engine, transmission. Then add any other pertinent info based on the actual question. That way it is much easier for us to help you. That being said, I agree that it sounds like either a bad/loose ground somewhere, a dead short with a wire touching a frame or other grounded item or a really bad starter. Starters can fail internally to the point where they become a big chunk of metal drawing a zillion amps. I'd pull the starter and have it tested first, then start looking for bad grounds and / or shorts. Good luck. It should be something you can find in one afternoon easily. :thumbsup:
 
I used to see guys "burn stuff up" quite regular back with lots of 4x4 roll bar lights were the rage, and winches. Vehicles are NEVER properly grounded to the frame/ body for large current flow. Guys would strap on a big Warn or other "wench" and promptly burn up the tiny body to battery cable.
 
harrisonm said:
@OhioJeremy, I see you are relatively new, so let me tell you something. When you ask a question about your car, we are HAPPY to help. However, it is very common for people (often newbies) to provide little or no information about the car. Regardless the question, I would provide year, make, model, engine, transmission. Then add any other pertinent info based on the actual question. That way it is much easier for us to help you. That being said, I agree that it sounds like either a bad/loose ground somewhere, a dead short with a wire touching a frame or other grounded item or a really bad starter. Starters can fail internally to the point where they become a big chunk of metal drawing a zillion amps. I'd pull the starter and have it tested first, then start looking for bad grounds and / or shorts. Good luck. It should be something you can find in one afternoon easily. :thumbsup:
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A zillion. Can you break that down for me? lol
 
I had a truck that the manual choke cable became my engine ground. I saw it steaming on a rainy day while engine was running. Someone probably me lol disconnected the engine ground and forgot to reattach it.
 
Saw a glowing shift cable due to a missing ground...

bad connection at battery, corrosion does that.
 
OhioJeremy said:
1968 barracuda, 318, 904. Thnx for help. Probably gonna need more.
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Assuming no one has monkeyed with the electrical system.
The power for the starter has its own path seperate from other stuff. So if it happened while attempting to turn the engine over, the problem was too much resistance for the amount of current. The two most likely causes are not exclusive, bad cable terminal and failing starter.
For more about how current flows when the key is turned to start, see this post.
Ground path for the starter is the transmission housing and engine block to the ground cable.
 
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Yup, either too much current draw, or too little gauge of ground wire......assuming it's connected straight from the battery to a clean engine casting.
 
cudamark said:
Yup, either too much current draw, or too little gauge of ground wire......assuming it's connected straight from the battery to a clean engine casting.
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I replaced the wire with 2 Awg so hopefully that helps.
 
Maybe. It would be nice to know what amperage the starter is drawing too. Most good shops will have a meter to test that with the starter still in the car.
 
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