TwoLaneBlackTop

Well, at 52K my alternator had died on my 1985 911 Carrera Turbo Look.

No big deal I figured any had it rebuilt. I then put it on and it seemed fine, but later that day the indicator light came on when the key was in off position and would stay on. So the alternator was dead after one day!

I took it out and back to the shop and they told me they were sorry about the trouble. I just put it back in and got evrything hooked up and no light when the car was off. I figured it was fine. Turn to ready and light comes on like it should. I turn the car over to assist with installing the belt and once I got it on right I started it and let it run. Low and behold THE LIGHT WAS STILL ON!!!! It would dim as I reved but would never go out. This means alternator is going bad or regulator has failed.

I am thinking there is somthing causing them to go bad. What could be killing these alternators like this or is it just the shops fault that rebuilt it.

scottb

For what it's worth, I once went through three alternators in my Acura within about 90 days. They were simply poorly rebuilt and kept failing. The current one (knock wood) seems to be OK. Of course, now that I've mentioned it here, it will fail next time I use the car. Damn Murphy is always there when you don't need him!

Good luck.

Face15

I assume you replaced the VR with the alternator? I just had a rebuilt alternator unit arrive with a faulty VR attached (internal on my 89 and supposed to be rebuilt as well), installed it and then found the problem. Ordered a new one from Pelican and haven't had any problems since pulling and replacing that.
Good Luck,

Steve Zitelli

If I remember correctly when the light stays on with the key off it indicates a bad VR.I was fortunate to have a good rebuild shop walking distance from my house.The person who rebuilt my alt. said it's wise to replace the VR when you replace the alt.If you don't you run the risk of a bad VR frying your new alt.

TwoLaneBlackTop

I was told they replaced the voltage regulator. It was to be included in what I paid. I am going to take it off and return it to them, if they dont fix it this time I am going to just get my money back and buy a new unit.

John D.

Earlier cars had a standalone voltage regulator - the later cars (the changeover was in MY 82 or 83, I believe) have an integrated regulator.

There have been several issues with "rebuilts" from several suppliers in the past where they will put in new brushes, bearings, check/replace the windings, etc. - but leave the old regulator installed. If you suspect it's the regulator - and it's on the later alternator type - they can also be replaced, but many mechanics simply replace the entire alternator, as it is easier to do and ship the old one back to the supplier on warranty. Sounds like you have two rebuilts in a row with a bad regulator, if yours is the later type...

Also - it's a good idea to check the ground points in the car - including the engine ground straps...

Brian911

First easy thing is to check the ground strap like John said. In my experiences, the voltage regulator was always the demon. If you are going through a Kragens, Autozone, or something like that, chances are you will not get the best product. I blew 8 alternators, 6 batteries and 4 voltage reuglators in two months on my old chevelle. I finally found one that worked though. If you do have a PEP Boys, they supply pretty reliable parts. If not there is always Pelican.

Brian
1980 911SC

Flat Six Addict

I recommend checking grounds, and then buying a new alt. My truck went through three rebuilds from CarQuest, Napa, and AutoZone. I gave up and bit the bullet and bought a new one about 40,000 miles ago. Haven't had any issues since. (Knock on Wood)