Grounding alternator

[pjm8047]

ive read its normal for old mopars to discharge with headlights on at idle. is it possible to add a 10 gauge wire between terminal 15 at bulkhead and the headlight and would it help the the alternator? the factory wire to headlights is a 16 gauge wire.

 

[oldbee]

Don't think it'll help, it's mostly nature of the beast on those low-amp alternators. They don't do much/any charging at idle; course we don't spend time 'at idle' right(?)!

 

[pjm8047]

Don't think it'll help, it's mostly nature of the beast on those low-amp alternators. They don't do much/any charging at idle; course we don't spend time 'at idle' right(?)!

True. What would happen if I disconnected the amp meter wire going to the starter solenoid? Already have a 10 gauge wire going from the alternator to that solenoid.

 

[Glenwood]

Do you mean starter relay?
Generally, the alt wire runs through the bulkhead to the ammeter. The other side of tje ammeter may supply power to items in the dash and then travel out to the starter relay, to charge the battery.
If you connected the alt directly to the starter relay, you've already bypassed the ammeter. Disconnecting the ammeter wire from the relay will disconnect power for the car essentially.

 

[pjm8047]

Do you mean starter relay?
Generally, the alt wire runs through the bulkhead to the ammeter. The other side of tje ammeter may supply power to items in the dash and then travel out to the starter relay, to charge the battery.
If you connected the alt directly to the starter relay, you've already bypassed the ammeter. Disconnecting the ammeter wire from the relay will disconnect power for the car essentially.

If i leave the factory alt wire on the alternator and disconnect it at the relay with a jumper running from the relay to the alternator im pretty much eliminating the amp meter right! The car should still have power its parallel circuit just remove a load.

 

[Glenwood]

If you have a wire from the alt directly to the relay, you still need the wire that connects from the relay post into the dash which is on the ammeter usually. This wire also travels through the bulkhead and can also be a source of problems causing voltage drop.
The only load rerouted as you suggested is to charge the battery. The remaining load for the rest of the car will still run through the wire from the relay to the ammeter.

 

[pjm8047]

Looking at wire diagram looks like if i were to disconnect the ammeter wire at the relay and ran a jumper to the alternator it will get power from the alternator the rest of the vehicle.

 

[pjm8047]

Just saw this thread at A-body forum Same problem im thinking
http://www.forabodiesonly.com/mopar/threads/dim-lights-at-idle.45546/

 

[Glenwood]

Sounds like you are trying to split the load between the car and the battery by running two separate wires from the alt.
I personally would not try that because if your alt dies or you lose the belt, your car will be dead and cannot run on the battery.

 

[pjm8047]

So I think I fixed the problem. I was reading that a bad ground could affect dim headlights at idle and other loads if there is a bad ground. So I checked the ground wire connecting the chassis to the battery and I found some paint on it and took a wire brush and cleaned it down and also cleared the ground going to the front headlights and other accessories i have connected to it. So I started the car up put it in gear And put the headlights on the voltmeter went down little bit but came back up to 14 V. I’m going to drive the car around the next couple days to test it out but I think that solved the problem.

 

[oldbee]

You might get lucky but mine did the same when brand new, especially if heater fan was on at the same time. You could just watch amp gauge going to the left!