High pitched whine. Alternator? 1973 Datsun 240z L24 Engine

[branham76]

So here is the deal. There is a high pitched whine when I accelerate. I was lead to believe it was a water pump problem so I replaced that. We ran it afterwards and the whine was still present. However we took off the belt that goes to the alternator and the fan and the whining/whirring was gone. What does this mean? Not sure what to do

[branham76]

I would like to add that the whining appeared out of nowhere about 300 miles ago

[5thhorsemann]

Same car, same motor. I thought that that wine was normal when I got the car. When I did the alternator upgrade to the 60 amp internally regulated unit, the wine was gone. If you do the upgrade when replacing the alt (reccomended), I would do the headlight relay upgrade at the same time to save your fuse box, the updated alt will cook it.

[branham76]

I believe the alternator I bought was 6o amp not positive though. I think the problem is the fan clutch now i am picking one up in the morning and hopefully it will work I will keep you informed

[Lazeum]

I've got the same issue with my car. It whines for 10s with the first revs when I get the car out of the garage then the whine stops.

I guess alternator gets load to charge the system after start up. My alternator is a rebuilt item.

Edited July 23, 2012 by Lazeum

[Wade Nelson]

Alternator bearings. Common.

Don't buy an Autozone $69 "lifetime" alternator. After you replace it FREE for the 3rd or 4th time you'll see why.

Buy a NAPA unit, or get your current unit rebuilt. Unless you like doing the same job over and over.

Put the two side by side on a scale and you'll see a good unit has 2-3X as much copper in it as the cheap Chinese alternator sold at AZ/Checker/Pep Boyz, etc.

[olzed]

I always get that high pitched whine. Especially when I corner or accelerate hard. Seems to come from the passenger side though. And almost as though someone is applying the brakes.

[branham76]

I got the 60 amp alternator I believe and it was mainly the fan clutch it purrs now thanks guys i was getting very irritated when it wouldn't go away!

[Lazeum]

Good to hear!

I will have to perform some test as well.

[branham76]

How does a fan clutch go bad?