Extra ground wire under the hood?
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Extra ground wire under the hood?
In my 80, there is an extra ground wire in the harness at the alternator that appears to go towards the nose of the car. I can't find it in the schematic and it is not the one that actually connects to the alternator lug.
Does anyone know what it actually connects and where it should be grounded? Are there two grounds that connect to the alternator? It looks official and I hate to leave it loose but at the same time I'm hesitant to just attach it somewhere.
Thanks!
Kim
Does anyone know what it actually connects and where it should be grounded? Are there two grounds that connect to the alternator? It looks official and I hate to leave it loose but at the same time I'm hesitant to just attach it somewhere.
Thanks!
Kim
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
In my 80, there is an extra ground wire in the harness at the alternator that appears to go towards the nose of the car. I can't find it in the schematic and it is not the one that actually connects to the alternator lug.
Does anyone know what it actually connects and where it should be grounded? Are there two grounds that connect to the alternator? It looks official and I hate to leave it loose but at the same time I'm hesitant to just attach it somewhere.
Thanks!
Kim
Does anyone know what it actually connects and where it should be grounded? Are there two grounds that connect to the alternator? It looks official and I hate to leave it loose but at the same time I'm hesitant to just attach it somewhere.
Thanks!
Kim
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Not the hood lamp, but good guess. My hood lamp has a red wire and a black wire in a separate harness that plugs into the main harness separately. The wire I am talking about is about twice the size of the lamp wires and goes back into the flex wrap heading forward. The only think up front is headlights, side markers, and horns. Everything works but the horns and I think they have bigger problems than a missing ground the gauge of this one.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You said "extra ground wire". Do you mean that there is more than one black wire coming from that alternator wiring bundle?
If only one, then, yes, that one goes to the [ground] stud connected to the backside of the alternator.
If only one, then, yes, that one goes to the [ground] stud connected to the backside of the alternator.
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
There is already one big ground wire on the alternator lug. There is also another one that is not bolted to anything that could easily bolt to the alternator. It runs forward in the wiring covers to ?
Safety Car
Joined: Jun 2004
Posts: 4,374
Likes: 223
From: Beecher Illinois
You keep mentioning alternator "lug".
Are you talking about the insulated one that the hot wire is supposed to go to? Should be a boot over it?
On all of mine the ground attaches where the bracket that some of the emission hoses goes through. Should be between the bracket and alternator with a star washer under the ground wire.
No "lug" for the ground.
You can just make out the ground wire under that bracket the hoses go through.............
Are you talking about the insulated one that the hot wire is supposed to go to? Should be a boot over it?
On all of mine the ground attaches where the bracket that some of the emission hoses goes through. Should be between the bracket and alternator with a star washer under the ground wire.
No "lug" for the ground.
You can just make out the ground wire under that bracket the hoses go through.............
Last edited by KapsSA; Feb 23, 2014 at 05:00 PM.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
Likes: 27
From: New Hill NC
You keep mentioning alternator "lug".
Are you talking about the insulated one that the hot wire is supposed to go to? Should be a boot over it?
On all of mine the ground attaches where the bracket that some of the emission hoses goes through. Should be between the bracket and alternator with a star washer under the ground wire.
No "lug" for the ground.
You can just make out the ground wire under that bracket the hoses go through.............
Are you talking about the insulated one that the hot wire is supposed to go to? Should be a boot over it?
On all of mine the ground attaches where the bracket that some of the emission hoses goes through. Should be between the bracket and alternator with a star washer under the ground wire.
No "lug" for the ground.
You can just make out the ground wire under that bracket the hoses go through.............
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Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
The wire goes into the wiring cover junction and heads towards the front of the car. The alternator ground comes out of the same harness as the main hot lead, which you can see below the master cylinder (the rusty part in the lower area of the picture). The wires that plug into the alternator come out of the harness that runs along the inner fender. The unknown ground also exits the harness there.
Last edited by CaseyJones; Feb 23, 2014 at 10:45 PM.
Safety Car
Joined: Jun 2004
Posts: 4,374
Likes: 223
From: Beecher Illinois
OK, so much for my theory.
But, I happen to have an 80 out in my barn for the winter.
Took a peek under the hood. He has BOTH black grounds going to the bolt on the back of the alternator.
Doesn't look right, tho.
The reach of that wire(won't reach rad support) and the size of the lug makes me THINK it goes to a 3/8" bolt somewhere near the front left of the motor.
This 80 also has headers, maybe went to an exhaust manifold bolt? Just spec.
Maybe start a new thread specifically asking 80 owners where it goes.
But, I happen to have an 80 out in my barn for the winter.
Took a peek under the hood. He has BOTH black grounds going to the bolt on the back of the alternator.
Doesn't look right, tho.
The reach of that wire(won't reach rad support) and the size of the lug makes me THINK it goes to a 3/8" bolt somewhere near the front left of the motor.
This 80 also has headers, maybe went to an exhaust manifold bolt? Just spec.
Maybe start a new thread specifically asking 80 owners where it goes.
Thread Starter
Melting Slicks
Joined: Jul 2010
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From: McGrady NC
St. Jude Donor '15-'16
When I bought the car it was so cobbled up that I couldn't tell right from wrong under the hood. I have managed to get everything working again so I can't figure out what it might do. Now that you mention it, I remember that it was connected to the alternator with the other ground. It didn't look right to me, either. The car was bone stock when I got it so any mods, including the headers, were added by me.
Thread Starter
Melting Slicks
Joined: Jul 2010
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From: McGrady NC
St. Jude Donor '15-'16
I actually have one and couldn't make hide nor hair of it. It includes the California 305 electronics and really confuses the issue.
I'm getting responses that that wire should connect with the big ground on the alternator. I'm going to try that.
thanks to everyone for your help!
Kim
I'm getting responses that that wire should connect with the big ground on the alternator. I'm going to try that.
thanks to everyone for your help!
Kim
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
That's the plan. I just wanted to know if it was original and if it indeed bolted on with the alternator ground. I've had several forum friends report that their 80's also have two ground wires on the alternator.
I just haven't figure out what circuit it belongs with since everything works without it except the horns, and it's a sizable ground wire for the horns.
I just haven't figure out what circuit it belongs with since everything works without it except the horns, and it's a sizable ground wire for the horns.
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
I have officially connected the extra ground wire to the alternator with the other ground wire as with the other 1980 owners have on their cars. It looks OK and no issues. I still want to know what circuit it services.
Thanks!
Thanks!