I believe, but am not sure, that I am getting no charging whatsoever (it was dark and the dash lights are not working. Not sure which, if any, of the dash gages are working - couldn't really see). I got the car started last night after replacing the ballast resistor and ignition module. But I ran the battery down pretty low over the weekend so it didn't have a whole lot left in it. I'm pretty sure the car was running on battery only. Anyway, I'm thinking alternator and/or the alternator voltage regulator. Any thoughts on this? Are the alternator rebuild kits at Auto Zone complete enough, or a waste of time?

Thanks for all your help. Oh, I'm new to this board and find it quite interesting and very, very helpful.

dave

There are only three things that go bad in an alternator. The brushes, the bearings and the diodes. (It's rare for a coil to fail.) Usually, it's the brushes that fail first. Rebuilding an alternator is fairly simple.

I'd verify that it's the alternator that's bad; it could be the voltage regulator. Recharge the battery and start the car.

If there's battery voltage on the field terminals; but, nothing on the output, then it's the alternator.

If there's nothing on the field terminals, then it's the regulator.

_________________
My truck is a Frankenstein creation
Built from the dead carcasses of others
And brought BACK TO LIFE!

Great! Thanks for that info. I'm going out of town for the weekend, but I will do that when I get back on Sunday, or maybe Monday. Thanks very much.

dave

You need to verify the rotor and or/stator did not short out. You can test for this with the alternator on the car. Whether on or off the car, the procedure is outlined in the shop manual. The brushes usually wear out before anything else fails. But still you need to check.

If you find the slip rings worn excessively, then you may as well replace the alternator because the alternative is to replace the rotor. This is expensive. I will tell you one thing about rebuilds: the slip rings came surface hardened from the factory. When the rebuilders cut them, the remove this hardening and often, the slip rings wear out faster. More important, however, when the slip rings wear at an accelerated rate, the resulting build-up and dust accumulates on the brushes and can create a short from the (+) brush to the alternator case. If this happens, you will burn up this wire straight back in the harness. I long ago put an inline fuse in the power wire to the brush right off the alternator. If anything like this happens, the fuse will blow.

Mitch

Mitch - thanks for the info. That is good to know about the slip rings. So, you are saying I shouldn't get a rebuilt alternator at the parts store because the slip rings have been cut? Sounds like an in-line fuse would be a good thing to do even with a new alternator, just in case. Thanks very much.

dave

A rebuild might give you many years of service. Each unit is build different with regard to how the slip rings are cut. If you take a light cut and depending on the depth of the surface hardening, you may still have a hardened surface remaining.

Mitch

Again, thanks Mitch. I'll try and test it when I get back into town on Sunday. It's been sitting for 10 years, a few more days won't matter - LOL.

Thanks, and have a great weekend.

dave