Motor ground gets hot

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Winchester

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Morning ya'll. I have a 85 C10 4x4, just put a new long block in. Hooked everything back up and tried to start it. When it turns over the ground strap from the firewall to the right rear of the engine gets hot and smokes. When I unhook the ground strap the starter just clicks. Never had this problem before, obviously something I did but I've traced the wires and can't find a short. Anyone else ever have this problem?
 

Winchester

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Yes the ground is clean. I unhooked it, it wasn't hooked up before I did the block swap but it always started. Can't find any frayed or broken wires anywhere. I looked for a couple hours yesterday before I got frustrated and called it a day!
 

Winchester

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I didn't think about that ground doing more than it's share of grounding. The battery ground is clean,no corrosion. I'll get back to it as soon as the rain stops, I don't have a shop or garage, doing it like a pine tree pitt crew. Thanks for the advice Ark-N-Saw,I'll let you know what I find!
 

MrMarty51

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Is the battery ground hooked to the frame or is it hooked to the engine ?
I always hook the ground to the engine then, take another grounding wire of the same size and run it to the frame, then, take another wire of the same size and hook it to the body from the frame ground. That way everybody happy. :Caffeine:
 

Camar068

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I'd replace the positive and negative cables.
Is the battery ground hooked to the frame or is it hooked to the engine ?
I always hook the ground to the engine then, take another grounding wire of the same size and run it to the frame, then, take another wire of the same size and hook it to the body from the frame ground. That way everybody happy. :Caffeine:

same here. I'd do that and change the positive going to the starter just in case.
 

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My truck did the same thing. Found that was the only ground from the engine block to the body, which also was the route to the frame as it was the only ground. Starter pulls lots of amps and needs a good, large ground.

I added a large battery ground cable from my frame battery ground to my alternator bracket, giving the system a good ground from the engine directly to the battery ground . No more heat or smoke from that small wire at the back of the cylinder head to the firewall.
 
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Winchester

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Thanks for the suggestions, I'm going to recheck all grounds and add a couple. I'll let ya'll know if it cranks up,burns up or blows up!
 

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I will send good thoughts your way. No burn down or blow up. Lol
Take it from a man who knows about smoking wires...
I don't mean 'smoking' wires... more like wires a smoking... no not standing there with a joint... oh never mind
 

Arkansas_V8

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Take it from a man who knows about smoking wires...
I don't mean 'smoking' wires... more like wires a smoking... no not standing there with a joint... oh never mind

That ignition wire fire I had was a pain in my butt. Lol
 

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My truck it did the same thing. Found that was the only ground from the engine block to the body, which also was the route to the frame as it was the only ground. Starter pulls lots of amps and needs a good, large ground.

I added a large battery ground cable from my frame battery ground to my alternator bracket, giving the system a good ground from the engine directly to the battery ground . No more heat or smoke from that small wire at the back of the cylinder head to the firewall.


^^^ What Dmack said ^^^
 

Matt69olds

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Just because the cable “looks” good, doesn’t mean it is. You can have corrosion inside the insulation where you can’t see it. Look on YouTube on the process of performing a voltage drop test. That’s the best and most accurate way to ensure electrical integrity.


Get it fixed, before you let the magic smoke out of the wires. Once the smoke is out, nothing electrical works.
 

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