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Discussion Starter · #1 ·
The small wire on my ground cable that attaches to the fender keeps getting hot.The first time I noticed it melted the outter layer and you could see the auctual wire.I then I put some electrial tape on it temperally and it also melted.Next I cut it and spliced an new wire still burned it through also.Could it be the ground cable?It only seem to get hot as you are started the car.I was doing a compression test and turning the engine and it burned up the wire twice.When you go out and start the car up without the it turning over alot before it starts its fine and doent melt the wire.

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The reason your little ground wire is getting hot is that it's carrying the load that should be carried by the LARGE negative cable. That simple. Check the point where the battery cable is grounded. Disconnect the negative cable from the battery AND the point where it's connected to the engine. Make sure that the connection is CLEAN and secure. If it's at the alternator bracket, be sure there is no paint under the bolt. If the smaller wire still gets hot after you've done these things, remove one of the exhaust manifold bolts and ground it under that bolt instead as a test. If everything returns to normal, then e-mail me. I'll walk you through what you'll have to do.

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MalibuJerry350
TC Member #1279
Original owner '70 Chevelle.
580,000+ miles on car.
Hey, if it's got wheels, DRIVE IT!
My Chevelle: http://hometown.aol.com/erie614/myhomepage/index.html
 

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Discussion Starter · #4 ·
Thanks guys for the replies.I do have it grounded to the head.I Will make sure there isnt any paint where I have it connected.I put a old cable on and it hasnt burned yet but it got alittle warm.Should that wire get warm at all??

Thanks again

[This message has been edited by 70RPOLS6 (edited 06-02-2002).]
 

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That little ground wire shouldn't get warm at all. As I had said, be absolutely sure that the large negative cable has a clean, secure connection. Also, be sure it's not so long that's coiled up on it's way to the grounding point. That just adds extra resistance.

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MalibuJerry350
TC Member #1279
Original owner '70 Chevelle.
580,000+ miles on car.
Hey, if it's got wheels, DRIVE IT!
My Chevelle: http://hometown.aol.com/erie614/myhomepage/index.html
 
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I agree with the replies on this subject matter. My 66 had the same trouble. I disconnected my ground wire from the battery ad the block. I cleaned the engine paint from the ground connection location on the block. Trouble fixed immediately.

Dwaine
66SS
 

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OK, (and yes i did read/sift thru all these threads starting from earliest to page 400 because) :

1) i want to learn about electricity and reading thru all these threads is soothing, interesting, and cozy, not to mention educational.

2) i figure it's better to read what's already out there first, instead of posting about my problmes. Saves space etc.

3) Additional NOte: Some people get all hysterical if a thread is more than a few months old-----"you're digging up an "old" post etc."
i don't know why people are like this? The topic is still relevant, so what difference does the date of the post make? In addition, as stated above, there are benefits to reading and responding to pre-existing posts rather than to make a new one.

So anyways, i'm having the exact same problem--my main, large negative battery cable grounds to the alternator bracket and the small ground wire branching off this large main wire grounds to the radiator core support and this small wire has the covering melted off. Note this melting happened pretty much right after i swapped in a differnt engine. Before this, no problems.

If we assume (thru testing with a multimeter) that this main cable as well as the small branch are good, then what could cause the alternator bracket not to ground good.

Has this happened to you? What advice do you have if any?
 

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OK, (and yes i did read/sift thru all these threads starting from earliest to page 400 because) :

1) i want to learn about electricity and reading thru all these threads is soothing, interesting, and cozy, not to mention educational.

2) i figure it's better to read what's already out there first, instead of posting about my problmes. Saves space etc.

3) Additional NOte: Some people get all hysterical if a thread is more than a few months old-----"you're digging up an "old" post etc."
i don't know why people are like this? The topic is still relevant, so what difference does the date of the post make? In addition, as stated above, there are benefits to reading and responding to pre-existing posts rather than to make a new one.

So anyways, i'm having the exact same problem--my main, large negative battery cable grounds to the alternator bracket and the small ground wire branching off this large main wire grounds to the radiator core support and this small wire has the covering melted off. Note this melting happened pretty much right after i swapped in a differnt engine. Before this, no problems.

If we assume (thru testing with a multimeter) that this main cable as well as the small branch are good, then what could cause the alternator bracket not to ground good.

Has this happened to you? What advice do you have if any?
What changed in your setup. Did you add electric fuel pump and fans. Try adding a large braided strap from the back of the engine to the firewall. Sounds like too much amperage being drawn though that small wire. Also check the cleanliness of your main ground wires and fastened securely.
 

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OK, (and yes i did read/sift thru all these threads starting from earliest to page 400 because) :

1) i want to learn about electricity and reading thru all these threads is soothing, interesting, and cozy, not to mention educational.

2) i figure it's better to read what's already out there first, instead of posting about my problmes. Saves space etc.

3) Additional NOte: Some people get all hysterical if a thread is more than a few months old-----"you're digging up an "old" post etc."
i don't know why people are like this? The topic is still relevant, so what difference does the date of the post make? In addition, as stated above, there are benefits to reading and responding to pre-existing posts rather than to make a new one.

So anyways, i'm having the exact same problem--my main, large negative battery cable grounds to the alternator bracket and the small ground wire branching off this large main wire grounds to the radiator core support and this small wire has the covering melted off. Note this melting happened pretty much right after i swapped in a different engine. Before this, no problems.

If we assume (through testing with a multimeter) that this main cable as well as the small branch are good, then what could cause the alternator bracket not to ground good.

Has this happened to you? What advice do you have if any?
Multimeters won't tell you if your battery cable and/or battery cable connections are good by measuring the ohms. You would need to have some one turn over the motor while you measure voltage from the battery negative terminal to the alternator bracket. If the voltage while starting is greater than 0.3 to 0.5 volts you have something wrong on cable or the the connection.

Ron
 

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1) Nothing changed except that actual engine block and i'm thinking, since the "new" one was painted over this might be part of the problem---the alt bracket may not be making good contact with the block.

2) i got a small braided wire from the cyl head to firewall

3) Please explain more about using voltage to test the battery cables; i should also mention that i cant crank the engine anymore either, no clicking either.
 

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1) Nothing changed except that actual engine block and i'm thinking, since the "new" one was painted over this might be part of the problem---the alt bracket may not be making good contact with the block.

2) i got a small braided wire from the cyl head to firewall

3) Please explain more about using voltage to test the battery cables; i should also mention that i cant crank the engine anymore either, no clicking either.
Something went open if you don't even hear clicking.

Is the small braided wire OK?

Do you have 12.6V or so at the battery posts? (at the posts, not at the cables)

If not battery is bad.

If you do have 12.6 V on the battery then disconnect the small wire that comes off the negative battery terminal and goes to the fender (this makes sure that the only path the current has to flow is the main battery cable), then turn on the headlights (The lights will act as a load). Even of they don't "glow", leave the switch on for the duration of the test described below.

Put one lead of a DVM on the positive battery post (not the cable connection).

Put the other lead on the alternator. You should have 12.6V.

If not work back towards the battery until you get 12.6V. First move to the alternator bracket, then to the end of the cable tied to the alternator bracket, then to the post connector on the battery (not the post). At the point you have 12.6V you have a complete circuit the otherside of that point where you have no voltage is the place where the circuit is open.

Why it is open you will have to figure out. it could be paint, it could be a battery cable that has internal corrosion you can't see, or it could be that a bolt is not tight.

This is the analytical way.

The other way is to disconnect and clean everything reassemble and see if it works.

Ron
 

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OK,thanks for the help; i will probably run these tests first thing in the afternoon since i'm on 3rd shift.

1) i do know that i got 12.64 at the battery--posts, so we know that's good.

2) i'm not exactly sure what a DVM is; i'm automotively challeged and electricity is a new world for me. Direct volt meter?
 

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OK,thanks for the help; i will probably run these tests first thing in the afternoon since i'm on 3rd shift.

1) i do know that i got 12.64 at the battery--posts, so we know that's good.

2) i'm not exactly sure what a DVM is; i'm automotively challeged and electricity is a new world for me. Direct volt meter?
Digital Volt Meter. You can get a cheap one at Radio Shack or get a Fluke, a good one from Granger or Fluke Directly. I have heard that harbor freight has them for five bucks; I wouldn't use one of those however.

Ron
 

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OK,thanks for the help; i will probably run these tests first thing in the afternoon since i'm on 3rd shift.

1) i do know that i got 12.64 at the battery--posts, so we know that's good.

2) i'm not exactly sure what a DVM is; i'm automotively challeged and electricity is a new world for me. Direct volt meter?
Digital Volt Meter. Forget about the braided wire, it's not designed to ground the engine and starter. Hook one up if the main cable doesn't have a good connection and it will fry, it can't handle the current. The negative battery cable is supposed to do that. Is it bolted to the block or alt bracket? If it's bolted to alt bracket it's harder to get a good connection. Need to clean paint off were cable is bolted to bracket. Then you have to clean off paint where the bracket bolts to the engine. Try using good star washers at those points. Bolted to head or block you only have one point of contact to worry about. You can get a good connection through the alt bracket. I just installed a powder coated alt bracket with ground cable bolted to it. Works great.
 

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I Always take a big battery cable hook it to the block then grind off a clean spot on frame to atach it aside from any other grounds to firewall I run one of these in addition
Has always worked for me
 

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OK, digital volt meter. i have 1 of those gauges sitting on the shelf. And i got an actron 7672 multimeter yesterday.

Anyways, i tried the thing that you suggested about taking the small branch wire off. And sure enough, no lights, cranking, dash lights, nothing.

i simultaneously noticed that the bolt on the alt bracket that fastens the large main negative battery cable to the bracket is basically stripped---you can barely tighten it down snug, then it pops loose.

So, i fiddled with it to try to get it tight enough to produce ground. And yes, it can if you're carefull. And i was able to start the engine. The engine stalled, probably due to the cold. And apparently, the vibration from this stalling (and possibly starting) caused the ground to again fail.

So, i think we may have isolated the problem. (the small wire was left unconnected during this "test").

So thanks again.
 

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I Always take a big battery cable hook it to the block then grind off a clean spot on frame to atach it aside from any other grounds to firewall I run one of these in addition
Has always worked for me
That's all good but if the ground cable from the battery to the engine doesn't have a good connection it doesn't matter. How does the ground current get back to the battery? You can hang grounds all over the place put some how the current has to get back to the battery. Don't expect that little wire connected to the fender or core support to carry 600 amps while starting the engine. That's the problem the OP had, that wire was trying to carry the starting current.

EDIT: What I'm trying to say is these cars worked good when they left the factory. 40 years later connections get corroded, parts get replaced or repainted and the original connections are lost. You can start adding additional grounds all over the place or fix the original ones. It's like saying this electrical outlet on this wall doesn't work. Instead of checking to make sure the wire connections are tight or replacing the outlet you run an extension cord from another outlet and say there, problem solved.
 

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OK, digital volt meter. i have 1 of those gauges sitting on the shelf. And i got an actron 7672 multimeter yesterday.

Anyways, i tried the thing that you suggested about taking the small branch wire off. And sure enough, no lights, cranking, dash lights, nothing.

i simultaneously noticed that the bolt on the alt bracket that fastens the large main negative battery cable to the bracket is basically stripped---you can barely tighten it down snug, then it pops loose.

So, i fiddled with it to try to get it tight enough to produce ground. And yes, it can if you're carefull. And i was able to start the engine. The engine stalled, probably due to the cold. And apparently, the vibration from this stalling (and possibly starting) caused the ground to again fail.

So, i think we may have isolated the problem. (the small wire was left unconnected during this "test").

So thanks again.
The ground bolt on your alternator bracket is a self-tapping bolt. Get rid of it, enlarge the hole slightly and install a regular bolt, with a lockwasher & nut on the bottom side of the bracket. Be sure to use the star washer under the new bolt head on the topside. Problem solved.
 

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The ground bolt on your alternator bracket is a self-tapping bolt. Get rid of it, enlarge the hole slightly and install a regular bolt, with a lockwasher & nut on the bottom side of the bracket. Be sure to use the star washer under the new bolt head on the topside. Problem solved.
That star washer is the key here too.
 

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I had this happen a month ago. The little wire had fallen onto my battery and nearly melted into the battery case!
Corrosion in the cable. If the cable is not supple and or makes cracking noises when bent then you have corrosion. New Cable is the right fix. My ground is to the engine, not the alt bracket.
 
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