View Full Version : One wire alternator....


deputyrob
09-10-2009, 07:35:06 PM
well, figuring my current alternator is more than likely kapoot, but am gonna have it tested tomorrow at NAPA. i was talkin to the parts guy at NAPA and suggested going with the one wire alternator. are there any pros or cons to the switch, and is it fairly easy. i get a little freaked out when it comes to messin around with the cars electrical system..dont want to cause my car not to start or somethin. whats the process in the switch. just cut the wire that has the two prong plug off and thats it?! couldn't be that simple.

stinkboy
09-10-2009, 07:52:13 PM
i wouldnt cut the wire i just wouldnt connect it so it would be able to be used at another time.

powermaster makes an alt that does both 1 and 3 wire which i have. 140 amps as well which most of the time handles my sound system. looks oem, and charges like a mofo.

markw
09-10-2009, 07:59:10 PM
Read this before you decide. http://www.madelectrical.com/electricaltech/onewire-threewire.shtml

deputyrob
09-10-2009, 08:13:43 PM
Markw..great info right there and thanks. think i'm gonna stay with the three wire alt. but heres one thing...the brown wire that runs from the plug to what i have been told is the idiot light was cut by a previous owner. is that going to cause me any problems..or is it no big deal.

Aceshigh
09-10-2009, 08:58:52 PM
think i'm gonna stay with the three wire alt.

I figured you would after reading that.

I have all of MAD Electricals booklets and kits I bought in 1 big kit last year.
Definitely a guy who knows what he's doing. I went 3 wire CS130 myself on both my classics.

deputyrob
09-10-2009, 09:14:42 PM
Aces..after that read was kinda a no-brainer. think i'm gonna hook up the idiot light also. more wiring fun!!

markw
09-10-2009, 09:22:30 PM
Try to fix the brown wire. That wire 'turns on' the alternator and it goes to the idiot light. The other side of the idiot light goes to 12v switched. If you just turn the key on the light comes on as current goes thru the bulb and then thru the alternator to ground. When the engine starts and the alternator starts charging the bulb now has 12v on both sides and the bulb stays off. I have heard that you can wire up a switched 12v wire thru a resistor in place of the idiot light, but I don't know how big a resister is needed.

deputyrob
09-10-2009, 09:46:30 PM
thanks for the info again...will try to rig up the brown wire.

deputyrob
09-10-2009, 09:50:15 PM
one other thing..if i can remember correctly...the previous owner has the red wire from the alt plug and the other red wire from the back of the alt running into one wire somewhere at the firewall. should i seperate the two wires? kinda seems rigged to me.

Aceshigh
09-10-2009, 09:53:15 PM
Try to fix the brown wire. That wire 'turns on' the alternator and it goes to the idiot light. The other side of the idiot light goes to 12v switched. If you just turn the key on the light comes on as current goes thru the bulb and then thru the alternator to ground. When the engine starts and the alternator starts charging the bulb now has 12v on both sides and the bulb stays off.

You know, i've been wondering how that worked myself for awhile now.....
Thanks for explaining it. Now I get it.

Been trying to figure out how the bulb shuts off for awhile now.