MONTE CARLO battery drain issue

Status
Not open for further replies.

BlueJay84

Not-quite-so-new-guy
Mar 6, 2021
8
0
1
Hello, I recently purchased a 1984 Monte Carlo SS and I'm having a battery drain issue. The original 305 was replaced with a 350. I've narrowed the issue down to the 2 wires connected to the alternator. One wire is a heavy gauge that goes to the battery, the other is a small gauge that goes into a wire harness but I'm not sure where it goes. When I disconnected them my test light went on then dimmed out within a few seconds. If I connect one wire at a time the test light won't come on. The test light only comes on when both wires are connected at the same time. Any help would be much appreciated
 

BlueJay84

Not-quite-so-new-guy
Mar 6, 2021
8
0
1
20210224_160536.jpg
 

pagrunt

Geezer
Sep 14, 2014
9,122
15,255
113
Elderton, Pa
You should have three wires on it: one brown about 16AWG that goes into the dash harness & (assume it's a factory gauge car) going to the resistor wire to excite the alternator, two red 12 AWG wires with one in the same plug as the brown & one on the stud on the rear with both wires tied into the same main feed wire of the same color & gauge off the starter running into the dash harnes/fuse box. Make sure this is correct as it's the easiest check to do before tearing things apart.
 

565bbchevy

Geezer
Aug 8, 2011
9,590
12,611
113
Michigan
This is what I'm working with
That looks like a 1 wire alternator, that black plug on the right is where a factory connector would plug into.
You should only need a large gauge charge wire going from the battery to the positive on the alternator.
You should also have a cover on the alternator terminal to protect it from accidently getting grounded.
 
Last edited:

BlueJay84

Not-quite-so-new-guy
Mar 6, 2021
8
0
1
That looks like a 1 wire alternator, that black plug on the right is where a factory connector would plug into.
You should only need a large gauge charge wire going from the battery to the positive on the alternator.
You should also have a cover on the alternator terminal to protect it from accidently getting grounded.
Thanks for the help, I removed the smaller gauge wire and that seems to have fixed the issue.
 

fleming442

Captain Tenneal
Dec 26, 2013
13,046
24,214
113
Thanks for the help, I removed the smaller gauge wire and that seems to have fixed the issue.
That's how I fix stuff- just unhook things until it works right without any troubleshooting. Get the 2 pin plug for the side and wire it correctly, chowderhead.
 
Status
Not open for further replies.

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor