Hi everyone, i was upgrading my cars electrical today (big 3, new 175a HO alt, Kinetik 1800w batt) and when I was done installing it and I turned over my car, I was running 13.8v. When I started playing some music, it sounded like it was quieter than when I had stock electrical. All the lights in my car were dimming and the volts were dropping as low as 10.5v. The alternator was charging real slow and having a lot or trouble keeping up. What could the problem be?? I am absolutely clueless on what it is so if anyone has a good suggestion, I would love to hear it. Thanks in advance

Provided you double checked the wiring and solid grounding, where did the alt come from?

Provided you double checked the wiring and solid grounding, where did the alt come from?

I'm gonna double check the grounds tomorrow. The alternator is a quality power alternator. That was the only brand that sold alternators for an isuzu trooper. Also, there was a wire connecting from the alternator to the main fuse box. I was told I didn't need that so I took it out and just had a wire going from the battery to alternator. Would that effect it at all?

I'd start by reinstalling that wire to the fuse box. It came from the factory so it may be needed.

I'd start by reinstalling that wire to the fuse box. It came from the factory so it may be needed.

i actually just went out and re-installed it. It actually got worse and the alternator didn't even seem like it was charging

Some alternators require a certain rpm to reach max output, is this when idling or driving when your volts drop down to 10.5?

Edited June 9, 201411 yr by Stephen93s10

Was there a wire from alt to fuse box then fuse box to batt?

I found the alternator that you are talking about but it doesn't specify how many amps it put out at idle or how many Rpms it takes to get 175 amps out of it either

Edited June 9, 201411 yr by Stephen93s10

When you have the time, you could go back to stock and make sure everything is working correctly. Then just change one thing at a time until the problem does, or doesn't show itself. Process of elimination should work here since you didn't do a ton of stuff at once.

Rev the engine, does the voltage go up? I'm guessing the HO alt makes less amperage at idle than the OEM alt.

Rev the engine, does the voltage go up? I'm guessing the HO alt makes less amperage at idle than the OEM alt.

That's also what I was thinking

Some alternators require a certain rpm to reach max output, is this when idling or driving when your volts drop down to 10.5?

it was idling when it dropped and it didn't seem to be recharging either. I did rev the engine a little to try to charge it and that didn't do anything.

Rev the engine, does the voltage go up? I'm guessing the HO alt makes less amperage at idle than the OEM alt.

i tried revving the engine and it didn't seem to be recharging it at all. Right now it seems like the alternator isn't working at all and the car is relying on just the battery.

When you have the time, you could go back to stock and make sure everything is working correctly. Then just change one thing at a time until the problem does, or doesn't show itself. Process of elimination should work here since you didn't do a ton of stuff at once.

yeah it's gonna be a pain to take the alternator back off though. It is in a horrible spot near the bottom of the engine. But if that's what it comes down to, I might have to put the stock back on

Was there a wire from alt to fuse box then fuse box to batt?

I'm trying to think if there was or not. From my memory, I think there was a wire connecting from alt to fuse box then fuse box to battery but il have to look into it later.

maybe your serpentine belt is to big? mine was doing something similar and I went and got a 1 inch smaller belt and it took right off.. the old belt must have been slipping a little or something but not noticeable to the eye

maybe your serpentine belt is to big? mine was doing something similar and I went and got a 1 inch smaller belt and it took right off.. the old belt must have been slipping a little or something but not noticeable to the eye

 

 Yeah, i see most h/o alts need a smaller sized belt like mentioned above. Have you checked into that yet?

maybe your serpentine belt is to big? mine was doing something similar and I went and got a 1 inch smaller belt and it took right off.. the old belt must have been slipping a little or something but not noticeable to the eye

i actually think that might be the problem. I installed a new Serpentine belt with the rest of the things yesterday. I just double checked all the connections and they seem to be tight. The alternator is actually keeping up with everything now but when I turned the music up, it seemed like all of the electrical cut off and reset while the engine is still running. It also cut off for a second when I put it in drive and started to go. I think it might be the serpentine belt slipping when I give the engine power.

Never remove when adding the big 3 upgrade. Just ADD.

Ok I think I found the problem. I bought these two battery terminals and It has 3 inputs for wire on each side and when you put the wire in, it is supposed to compress the wire and make it a better connection. It doesn't fit on the battery snug enough and the wires are so loose I could pull them out of where it is supposed to compress the wires. I'm going to take the battery terminals off tomorrow and just hook the wire up straight to the battery. Right now, I re-tightened the terminals and I can play my music loud without it cutting out and the alternator is keeping up a little better but if I turn the bass up all the way, my volts drop down to as low as 10v. When I turn the music off, the volts shoot back up to 13.8v. Before I even installed the alt, batt, and big 3, my volts were running around 14.3 and it would only drop to around 12-11 volts when there was a ton of bass. Hopefully when I hook the wires up without the fancy 3 way terminals, I will be getting the full power.