Well my alternator crapped out But the more i think of it the more i think it may not have been charging since i put it on but I'm not sure. Do you have to do any thing wierd with these when you hook them up like run 12v to the exciter terminal then hook the exciter wire up? I think you had to do that on some older ones to set the pollarity?

 

That's an externally-regulated one, right? That's some old tech there, ditch it and install 130 amp 3G alternator in its place, it ends up just a two-wire setup (battery charge and key-on trigger) and you got more power than you (at least for now) know what to do with. I'll try to see if I can trace some of the factory wiring in my truck and figure out which wire goes to what tho, just in case. Or, you can give these guys a call, and see what they can do for you, their prices are steadily lower than what parts stores will charge you for a 3G alternator: Motor City Reman - High Performance Starters and High Amp/High Output Alternators

 

george check your voltage regulator too those things are known to go bad on these trucks, me and my dad had this trouble on his truck a few years back, turns out our alternator went bad and that burned the regulator out, so a new alternator and a new regulator fixed every thing, 30 dollars for the voltage regulator and 90dollars for an alternator is what it costed us

 

No as far as I know its internal well I'm goign to go see if i can get it started

 

You just hook it up and it should run. Have you put a volt meter across the battery terminals (one of the batteries) to see what the volts are with the engine running. Should be around 13.5-14V?

 

You know what George, I'm an idiot, with that '94 you already have the good alternator. Here's what the wires are for its plug: - yellow = battery voltage sensing wire, gets constant 12V from one of the batteries - green = alt trigger wire, gets 12V key-on power - white/purple = rectifier exciter wire, or something like that, gets plugged on the side of the alternator. So essentially if you get battery power at the yellow, key-on at the green, and some continuity (low resistance) when you measure between plugs across the white/purple wire, then your harness is just fine, and your alternator was faulty.

 

I personally like the external regulator... 20 dollars and two easy bolts and its replaced... the internally regulated alt's require removal of the alternator and taking it apart to fix...just MHO...lol

 

Actualy it turned out to be externaly regulated the regulator is on the back of the alternator. It was the alternator or atleast the regulator I had the alternator but had to wait till tomarow if i wanted to just get a regulator so I didn't take the time to check it I just check the volage to the regulator the out put voltage and volt drop of the charge wire to battery.