Alternator woes

[euroz06]

Hi All,

I have installed a 2 pulley high amp alternator, and I'm having a ton of issues. I am not sure if I'm stupid, or if the alternator is not the right one for me. I previously had a single pulley alternator that worked very well, but because I have factory AC, a two pulley one was needed.

So recently I ended up driving at night, and noticed that all my lights are fluctuating in brightness (including headlights). Its not only when idling, but also when driving and rpm's are high.

My volt meter and oil pressure meter stopped working as well (the manufacturer had me run 8GA wire from the alternator to the battery, but i still ran the stock skinny wire to the junction box, i.e. i didn't remove anything, just ran an additional wire to the battery).

Any advice is appreciated. Its a 68 charger, 383, all stock

 

[pnora]

Sounds like a regulation problem.

 

[66Satellite47]

Be sure the voltage regulator has a good ground. The wire to the bulkhead and it's connection is also a very likely issue.

 

[euroz06]

When I installed it, I didn't change anything/touch anything. All I did was replaced the alternator (same brand, so all plugs were the same), all wires stayed in the same place. The only thing I did was add an 4 GA (wrote mistakenly 8 above) wire from the side post of the alternator directly to the battery. All the other wires that ran to the bulkhead stayed in place.

My voltage regulator is not connected, my understanding is that I have an internal one in the alternator (its quality power brand).

 

[AR67GTX]

Deleted - if high amp not stock.

 

[pnora]

When I installed it, I didn't change anything/touch anything. All I did was replaced the alternator (same brand, so all plugs were the same), all wires stayed in the same place. The only thing I did was add an 4 GA (wrote mistakenly 8 above) wire from the side post of the alternator directly to the battery. All the other wires that ran to the bulkhead stayed in place.

My voltage regulator is not connected, my understanding is that I have an internal one in the alternator (its quality power brand).

Then it sounds to me like an alternator issue as the regulator is built in. You need to clarify what you have when starting to post a problem. Other wise you will get non pertinent replies.

 

[66Satellite47]

What does the 4Ga wire connect to? That's a huge wire.
EDIT: the 4 ga goes directly from the alt stud to the battery?

 

[euroz06]

Apologies gents, I should have been clearer.

initially when I installed, I just did a plug and play, and when I started the car, the alternator was making a whine. I reached to the company, they told me I need to upgrade the wire and instructed me to run that 4GA from the side post. When I did that, the whine stopped, but then I started to have issues with alt meter not working, and oil pressure gauge being lethargic… I was goI got to be fine with that, but this fluctuating light thing is a no go.

im ready to send them another email, but I dont understand enough about this topic to be confident and tell them wtf. I deeply regret this ”upgrade” at this point, I should have just upgraded to dual pulley on my old alternator, but I live in Miami and have low confidence in local shops to do it right.

 

[LowBikeMike]

If you are running a wire directly from the Alternator to the Battery your Ammeter is not going to operate properly as you have noted.

 

[pnora]

I would put a volt meter on the battery when it is acting up and see what it says. If the voltage is fluctuating then it is most likely in the alternator.

As said running the wire from the alternator to the battery is by-passing the ammeter. So its not going to work.

Oil gauge could be a bad sender or loose wire on the sender. You may of knocked it loose running that wire.

 

[euroz06]

ok, so I need to look at the batter when light are on to see if the voltage is stable, got it. if its not, then its the alternator.

how do I make the alt meter work correctly?

I should have clarified, the oil pressure gauge works, but its very lethargic, i.e. in the past it would react to my gas pedal, but now it just kind of limps around showing random stuff.

 

[pnora]

The ammeter will never work correctly with the wire from the alternator going direct to the battery. Myself I would completely bypass the problematic ammeter and go with a volt meter.
Oil pressure easiest attempt would be a new sending unit. You might also consider testing the pressure with a mechanical gauge to make sure you do not have an oiling problem.