Electrical issues

[SKI-'84K5]

Well today i was headed out to the brother in laws and the voltmeter started fluctuating pretty good back and forth between about 13 and right at the low end of the "overcharging" orange section. When i got there the battery was looking pretty rough, like it had been seeping around the caps on top.

Pulled it and went to an Autozone to get a new battery and on the ride home the voltage was not jumpy but stayed to the high side of the gauge but not quite overcharging. I have the feeling that the regulator in the alternator is shot and I do have an extra one in the garage but won't have a chance to swap it out until at least tomorrow.

Any other ideas to throw out there before I start messing with it?

Thanks in advance.

 

[Fordum]

Yep, grounds. Make sure the voltage reg has a good ground. If its in the alt. make sure its grounded. Don't assume because its bolted tight that its making a good connection. For a quick test, run a 10 ga or so wire from the alt body to the neg. post of the bat and see if it settles down. This is more common with remote regs, but the built in ones do it too.

 

[bot0611]

I got a question, where is the regulator located on an external regulator atl??

 

[76zimmer]

inside a black box

, like this

 

[bot0611]

I know thats the external regulator but where does an 81-87 chevy truck have it?? in the my alt has 3 wires but ive never seen the regulator nor out or inside the cab

 

[Fordum]

Probably doesn't have an external on that year, but I didn't know the year at first. If it does have one, it usually on the fenderwell somewhere.
Either way, check the ground on the alt.

 

[76zimmer]

I know thats the external regulator but where does an 81-87 chevy truck have it?? in the my alt has 3 wires but ive never seen the regulator nor out or inside the cab

Your truck shouldn't have an external reg.

 

[SKI-'84K5]

Should have mentioned it's an 86 burb. A month or so ago I did replace the low beam harnesses and replaced some of the grounds as well as add an extra 4 gauge from the alt to the frame, I will add another short length from the frame grounding point to the neg on the battery as well before i change out the alt just for SNG.

Thanks everyone.

 

[scooter122983]

This is perfect, I get a answer to a question that I was just about to post today. My volt gauge reads right around 13-14 but right about when i get home my gauge is topped out. I just recently replaced a 1 wire with a stocker and was good untill a couple of days ago. The stocker has the pole for the ground wire but i didnt use it not realizing what it was.

 

[dogsofwar]

Voltmeter reading

Mine also hangs around 13-14, is this normal?
(85 blazer)

 

[dyeager535]

13-14 is normal/good. Really need to measure at the alternator though, to make sure output is reflected *proportionately* (while not numerically accurate, as long as it shows voltage swings, it is valuable info) at the gauge.