79 rx7, running the Banzai Racing Dual Sheeve Alternator pulley and matching belts, because I had a belt squeal with only 1 pulley. No air pump. Water pump and Alt are basically brand new.

New double belts are worn in, properly tightened, still squealing. Only does it at big throttle inputs, above 5500 rpm, mostly in first and second, but sometimes in third.

I don't really have any overheating issues, but I can barely get a quarter of a turn out of the fan spinning it by hand fully cooled down. I suppose I don't have any overheating issues because the fan clutch is probably more engaged than it should be versus the opposite.

The squeal happens less when it's cooler out, around 50 degrees and it'll only really squeal after I've been sitting stopped for a while.

This sound about par for the course of a failing fan clutch?

 

I don't have the double, but mine squeals in first and second too. I replaced the clutch fan with no change. Way back in the day 86-87, my first rx7 never squealed. Maybe the they make belts these days. I'm sure the aren't made as well today. I use Gates, which are supposed to be good.

 

Well, I went back out and loosened the belt tension and the squeal started 600 or so rpm earlier and carried all the way up. Tightened it back up and then some and the squeal just started 600 or so rpm later.

After getting back from the drive the fan was noticeably harder to spin by hand but only by a little. So probably not the that given how I don't have overheating issues.

I've got Gates belts as well. I dunno. It sure is annoying not being able to hear the engine when it's sounding it's best.

 

Theres only 2 things it could be; the alternator or the fan/waterpump. Drive it without the fan and see what it does. Check the alternator voltage and make sure your battery is up to snuff. It could be trying to charge all the time for instance.

 

Do you mean remove the fan blades or the whole fan and fan clutch assembly from the water pump?

Alternator is for sure solid.

 

Removed fan assembly and took it for a drive. No more belt squeal. Hmm. I suppose my best bet is to post a WTB for a used one?

 

Posted a WTB for a 79 fan clutch in the new marketplace if anyone's got one they want to sell. Thanks!

https://www.rx7club.com/market/1147368

 

After giving my fan a test with a broom, 10-20 seconds into start up. I can stop it with a broom. I'm thinking maybe the fan isn't bad, but the squeal is 100% caused by the fan. Maybe it's just barely malfunctioning?

 

Belt squeal is usually caused by belts. Mine never squeal but they fly off If I ignore my buzzer!

 

Are you sure they are tight enough? That sounds hilarious though.

 

I have the same squeal issue on my 83 GSL, but with factory single pulley and I removed the AC compressor. Alternator is new, belts are new and plenty tight. The only way to get the squeal to stop was to remove the fan/clutch. So I found one at a wrecking yard and put that on. The squeal was back! It's been two years since I fiddled with it. I just learned to live with it and not worry about sounding silly on the autocross course. But I'll be watching this thread to see if you have better luck than I did.