I'm at my wits end with this. Took the alternator out because it was fluctuating between 12 and 16 volts depending on the rpm and put a new voltage regulator in. Voltage stayed solid at 14 the entire trip, until the home stretch when it just dropped to 12 and stayed there. Idiot light has stayed on since. So, I ripped it out again and pulled it apart, and tested the components as it says in the service manual. Everything checked out except for the rectifier, which gave me nothing when I should have been seeing resistance one way and not the other. Nothing either way. Ordered a new one and put it in today, same thing happening. Not even budging above 12v. I honestly don't know what else it would be and I'm just about ready to take it out and throw it off a bridge. Ideally I messed up when I put the alternator back together, I really hope that's it. I'm tired of spending money on an old alternator to the point where I might as well buy a new one. It's a Delco 10SI for reference. Any suggestions would be appreciated. Thanks
I would think there’s a rebuilder in your area who can do these in a day with his eyes closed. (My guy is about $90 with a one day turn). I’d ask around or google search. His shop will be cluttered and grungy and he’ll have piles of weird stuff like LeeceNeville ambulance units and diesel starters; that’s how you’ll know you’ve found the right guy (or gal!). You may have made an error or you may have gotten junk parts. He can advise you. Patrick
The guy I went to to get the little plastic insulator the first time around would fit that description. Will have to give him a call I guess. Too bad, I was hoping it would be easy enough to do at home but I guess it’s above my pay grade!
Want to update this because as much as I feel like a dolt, it's good information. I got my alternator back from the shop today, guy says that everything inside was too loose. Not just one thing, everything. Needless to say I'll be checking that first if I have problems again. I'm very impressed with the guy I took it to. He could have fleeced me for such an easy fix and told me it was something big and expensive, but he didn't. He laughed with me when I was giving myself hell for not tightening anything down enough. I'll be going back if I need to, and sending anyone and everyone who mentions an alternator or a starter to this guy. Very happy with the outcome despite the fix being right in front of me!