So my father has had an 88 Camero convertible for quite some time now. Great condition only 60,000 original miles. It has now become mine and there only seems to be one issue. The alternator is getting red hot. I know a fair amount about cars so this is making think that maybe something is grounding out? Or maybe a high output alternator was installed? Any thoughts would help. Not sure where to start.

 

Have you tried replacing the alternator?

 

Not positive what a "Camero" is; but in case it's anything like a Camaro, I'll speak to that.

The alt being defective can cause that. Probably not the most likely thing but definitely possible.

Usual cause of it is, a shorted cell in the battery. The voltage regulator will see the system voltage being too low, and will attempt to command the alt to produce enough power to raise it. If the batt has a shorted cell, the voltage will be about 5/6 of what it should be (a batt has 6 cells, each producing about 2.2 volts at no load), and the alt will work its butt off trying to make up the difference. It will generate its max possible output 100% of the time but still be unable to keep up.

First thing I'd suggest doing is, measure the voltage across the batt terminals while the engine is running. Should be somewhere near 14V. If it's lower than that, particularly if it's in the neighborhood of 11.7V or so, then the alt is probably fine, and it needs a batt.

If it's above 13V but not more than about 14V, then the alt is probably at fault. Measure the AC voltage at the Big Red Post on the back of the alt. Should be less than 0.3V or so. If it's more than that, then it probably has a shorted diode (or more than one) in the rectifier, and it's time for an alt.

If it's above 14V, then either the regulator has gone bad, or the wire connected to the S lead (in the small connector) is disconnected; and the regulator inside the alt is commanding full output to try and raise it to its target of roughly14V. But if the wire is disconnected it will NEVER see that much voltage since there will be no voltage at all on it, so the alt will go into screaming overload trying to make it so. Bad regulator = needs an alt. Wire disconnected = find the broken or loose connection, which might take some hunting.

 

The alternator can safely run upto 15 volts. Old school was 14.2 as a standard - 1970's

 

A lead-acid battery runs at the voltage it runs at. The alt has to match.

Not a matter of "old school"; simple physics & chemistry.

 

Alternators do run hot, so to a point that is normal. Hot enough to not want to touch one.

But, as sofa posted, a bad or weak battery will put an additional strain on an alternator. If your car has the CS130 (an '88 has a good chance it is), they are notorious for overheating and popping the rectifier bridge. BTDT, on a weak battery, hot rainy night, and stop & go traffic.

There used to be, maybe still is, a replacement rear case-rebuild kit for them. The case has heat sink fins along with the kit having a better rectifier. It was an Ice-something or other. And make sure that the rear of the case is open, not being blocked, as that is where the cooling air is drawn in.

RBob.

 

That would be the CS-130D Back-half.

Some have the larger size 130D Bearing...
That is the one you want to find.

Now most places upgrade the CS-130 with the Components from the AD230 Model.

 

I figured it out, the Iceberg case. It is the back half with cooling fins. Still available along with the rebuild part kit. Need to be rather mechanically inclined to do a rebuild on the CS130, as they are not designed to be rebuilt.

RBob.