DUAL BATTERIES KILLING ALTERNATOR (1 Viewer)

[HEAVYDLX470]

So I put a dual battery setup in my 2005 LX about 8-10 weeks ago about 4 to 5 weeks later my alternator let out (was the original) replaced it with OE and now it went out again.
The dual batteries are wired up with a dual battery isolator, just like everyone else on here has it wired.

1= Think I just got a bad alternator?

2= Think something in the wiring for the dual batteries?

 

[vman07]

Are your two batteries automatically linked and receiving an alternator charge when the car is running? I incorporated a manual switch on my solenoid to be able to link, or not link, my batteries at any time.

I don't generally link my batteries with the LX running unless the trip is going to be more than like half an hour...

 

[HEAVYDLX470]

Are your two batteries automatically linked and receiving an alternator charge when the car is running? I incorporated a manual switch on my solenoid to be able to link, or not link, my batteries at any time.

I don't generally link my batteries with the LX running unless the trip is going to be more than like half an hour...

They are hooked up to a isolator that links them when the truck is running.

 

[gatormark91]

New batteries, I assume? Could be one of the batteries is faulty. Maybe try running it on just the starting battery for a bit and see how it does. What sort of voltage are you seeing on the two batteries when they are attached, and on each isolated? Obviously, test the voltage on the one that is still being charged when the truck is on, and when it is off. The two batteries should have the same voltage when isolated and attached when the truck is off.

 

[diego355]

What dual battery system do you have? Can you post a diagram of hat you have?
I'm suspecting there is a fault on your system

 

[HEAVYDLX470]

What dual battery system do you have? Can you post a diagram of hat you have?
I'm suspecting there is a fault on your system

 

[HEAVYDLX470]

Its basically like that. The only thing I can think is that the wire I used to jump to the isolater is the wire coming from the alt to the truck battery and making the alt think it needs to run as hard as it can all the time? But don't know.

 

[gatormark91]

Its basically like that. The only thing I can think is that the wire I used to jump to the isolater is the wire coming from the alt to the truck battery and making the alt think it needs to run as hard as it can all the time? But don't know.

View attachment 1702299

Sounds like you tapped into the alternator charging wire going to the battery? If so, don't do that. Attach the second battery + charging wire to the terminal on the battery directly, not to any other wire. Some photos of what you did,with some explanation, would be helpful.

 

[HEAVYDLX470]

Sounds like you tapped into the alternator charging wire going to the battery? If so, don't do that. Attach the second battery + charging wire to the terminal on the battery directly, not to any other wire. Some photos of what you did,with some explanation, would be helpful.

The batteries are hooked up + to + with the isolater in betweenthwm, but the wire that tells the isolater to turn on is hooked into the wire coming from the alt. Can't get any pictures truck is at the shop.

 

[gatormark91]

The batteries are hooked up + to + with the isolater in betweenthwm, but the wire that tells the isolater to turn on is hooked into the wire coming from the alt. Can't get any pictures truck is at the shop.

Try keyed hot power to turn on isolator, and leave the alt wire alone. That power lead isn't going through the fusible link to the battery. It could possibly be causing problem with the field in the alternator, causing it to work too hard to keep the voltage in the right range.

 

[HEAVYDLX470]

Try keyed hot power to turn on isolator, and leave the alt wire alone. That power lead isn't going through the fusible link to the battery. It could possibly be causing problem with the field in the alternator, causing it to work too hard to keep the voltage in the right range.

That's what I'm hoping is the problem going to run some test tomorrow with the new alt on it, me and the wife are leaving to do the KAT Saturday for our honeymoon/one year so hopefully I get it figured out.
Thank you for anyone's help.

 

[HEAVYDLX470]

So we got it figured out, basically what happened is the wire I tipped into to kick the isolater on, was the voltage regulator wire coming from the alternator. Dumb mistake I know.

Thanks for anyone's input again.