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NEW QUESTION AGAIN...ground wire

  • Thread starter Thread starter 1970impala
  • Start date Start date May 20, 2004

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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May 20, 2004
#1
  • May 20, 2004
  • #1
I just seen a picture with a ground wire attached to the firewall behind the battery. where does the other end of that ground wire go to?
 

Mstng2

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#2
  • May 20, 2004
  • #2
Some of the original II's had a double ground neg. battery cable. It goes from neg post on battery to firewall, then continues to the engine block and bolts to the back of the heads. This was done to ground the body (for radio etc) and the engine both.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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May 20, 2004
#3
  • May 20, 2004
  • #3
Mstng2 said:
Some of the original II's had a double ground neg. battery cable. It goes from neg post on battery to firewall, then continues to the engine block and bolts to the back of the heads. This was done to ground the body (for radio etc) and the engine both.
Click to expand...

so was the thin black wire that connects to the firewall directly attached to the ground cable..and if so..where? i have an original ground strap that was already on the car when i got it and it bolts to the heads but i don't recall seeing a small black wire....is that supposed to go to the black cable too????
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
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Sep 1, 1998
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May 20, 2004
#4
  • May 20, 2004
  • #4
You misunderstand.


The tag that was 'bolted' to the firewall was like a clamp in the middle of the cable. The ground went from the battery through this clamp then to the back of the head.

You don't want one of these. Due to engine rock and the shortness of the cable between the head and firewall the cable tended to fail (usually electrically) at the clamp.

But then you are Mr. Concourse. If I were you I would put it in a box and use a better ground setup and only install the factory cable when it matters. Like when it's being judged.
 

Power Surge

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Jul 20, 2002
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May 20, 2004
#5
  • May 20, 2004
  • #5
Jon, the factory ground cable has a tab clamp halfway through it, that attaches to the firewall. At first I thought it shared a heater box stud, until I saw a car with an original cable on it. There was a hole in the firewall for a self tapping screw that never noticed. That's where it went. The other end goes to the back of the head. I had an NOS cable on my 76, but it was for a 4 cylinder, as I could not find a V8 one. The only diff was that it was a few inches longer than the V8 one. But Phil owes me a replacement repro neg cable, if you want it, it's yours.

This is a pic of my 76 that I think may help answer some of your questions about the ground tab and stuff:

 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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#6
  • May 20, 2004
  • #6
CobraIILover said:
Jon, the factory ground cable has a tab clamp halfway through it, that attaches to the firewall. At first I thought it shared a heater box stud, until I saw a car with an original cable on it. There was a hole in the firewall for a self tapping screw that never noticed. That's where it went. The other end goes to the back of the head. I had an NOS cable on my 76, but it was for a 4 cylinder, as I could not find a V8 one. The only diff was that it was a few inches longer than the V8 one. But Phil owes me a replacement repro neg cable, if you want it, it's yours.

This is a pic of my 76 that I think may help answer some of your questions about the ground tab and stuff:

Click to expand...

SAL, GOOD. THIS IS THE PIC I WAS REFERRING TO THAT I WAS LOOKING AT THIS MORNING.....take a look next to the copper ground strap on the firewall. what the heck is that skinny wire next to it? its a ground but where does it go???? i know about the plate 1/2 way through and mine is connected to all that and at the end but i don't have that black wire there in the pic. i only have a screw there..what is that?
 

Power Surge

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#7
  • May 20, 2004
  • #7
If I recall, that was the ground wire for the blower motor. My car was a non-A/C car. I "think" on A/C cars, which I think yours is, it doesn't use that as the whole heater box/blower motor assy is different.
 
T

THE COBRAMAN

pig 'rassler
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May 20, 2004
#8
  • May 20, 2004
  • #8
Ground wire for the heater blower motor on non-A/C cars.

A/C cars have that wire under the dash in the harness.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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May 21, 2004
#9
  • May 21, 2004
  • #9
THE COBRAMAN said:
Ground wire for the heater blower motor on non-A/C cars.

A/C cars have that wire under the dash in the harness.
Click to expand...


You guys on here are the best! i couldn't work on this car without you.
 
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