[Obi-Wan]

My neighbor has a '95 Windstar with the 3.8L V6. The alternator wasn't charging the battery, which caused the battery to die. On the advice of the genius at Jiffy-Lube, he bought a new battery yesterday, but of course that didn't help. I dug out my multimeter today and verified that the new battery had 12.2V, but the positive terminal on the alternator only measured about 11.8V. Tried replacing the regulator, but that didn't help. We put a "new" rebuilt alternator in for $140, ran the engine for about 20 seconds, and measured a steady 14.5V at the positive alternator terminal. We declared the operation a success, and I packed up my tools and went home.

Later this afternoon, after less than 30 minutes of driving around town, the battery had drained so low that the engine died just 3 blocks from home. After a quick jump start and a short drive home, I measured 11.5V on the battery. Turning the key just clicked the starter. We jump started it again to get the alternator turning, and with the other vehicle still connected via jumper cables, I measured just 12.2V at the alternator's positive terminal. The new alternator obviously had stopped charging again.

Any ideas what could be causing this? The alternator worked briefly when it was first installed, but obviously quit soon after. Is there something else in the vehicle that could cause the stator not to turn on? Where do the stator & field signals come from? The wires just disappear into a huge harness and I lost track of them.

We don't have a manual of any sort for this Windstar, and my neighbor's extremely short on cash, so he doesn't want to buy anything he doesn't have to (including a $140 alternator that doesn't fix the problem). He also really needs the vehicle to be running when he goes to work on Monday, so he didn't want to wait until the work week to take it to a mechanic and then pay outragous labor costs.

I'm a decent shade tree mechanic, but I mostly know Jeeps, and by this point, I'm at a loss without a service manual of some sort. Any help would be greatly appreciated!