Ok, so in the 85 Z28 5spd (LG4), it would squeal on startup, sounding like a slipping belt, we adjusted the belts, yet it solved nothing... it would also squeal around 3500rpms, later i noticed that on startup the squeal would be there and the volts were low, and the squeal would stop after the volts came back up(after about 5-10 sec), so i figured the alternator was bad? So we changed the Alt, and the squeal at startup appears to be gone, yet the squeal at 3500+rpms, is still there... The car has no a/c (we took it off) and no smog pump either..., we had the belt off of the power steering pump when this problem arrised(it's been off for three months now and the squealing just started)... So the only belt left was the one that went arround the crank, water pump, and Alt... we put a new Alt on like i said, we also replaced the water pump, and replaced the belts, and put the belt back on for the power steering... Any Ideas as to why its squealing? Thanks in advance for your help...

 

Once a belt has slipped, it glazes the gripping surface of it, and
will always squeal afterwords. Buy a good quality new belt
(read: Goodyear or Gates), adjust it correctly and you should
be good to go. If you have an automatic belt tensioner, and it
has more than 30,000 on it, bag it too. They aren't designed to
last forever, the spring has no cooling or lubrication and the
bearing in the pulley has only the grease that comes in a sealed
unit (not much), and also gets pretty hot. I'd buy that unit at GM
as the aftermarket units suck (believe me I sell them....I also
sell Dayco belts which I won't reccommend...)

 

thanks, we did replace the belts, but i'll check in the morning the brand, its a v-belt not serpintine, so theres no tensioner...

 

O.k.-sorry didn't catch the '85-was too busy checkin' out your
'96!

If you have a power adder that makes RPM's come up real fast,
this can happen too. I had an 8-71 on a 454 in my '84 Z-28 that
would cause good quality belts to launch off and take out my
very expensive Gilmer blower drive belt! I put on a Checker flag
special to milk it home with, and to my suprise it would just spin
on the pulleys when I nailed it instead of launching off! This is
the one case where a cheap belt was better!

Also, make sure the pulleys are lined up perfectly. Sometimes
alternator manufacturers put the wrong spacer behind the pulley
and move it by 1/8".....not enough to notice.

Buy a Goodyear if you can, tighten it normally, drive it without
mellow for a while, and re-adjust it. You may also want to take
some fine emory cloth to your pulleys to make sure no melted
rubber remains.

Good luck!

 

Thanks again, the 85 is bone stock cep for the flowmaster and 1LE Alum driveshaft i took off my 96... which btw is awaiting a 400cid LT4 that will be built to handle twin rear mount T3/T4 hybrid turbos(STS style)... So thats were most of the money is going now, I have a fresh block for that project, then I will build the old LT1 up mabe to 396cid to stuff in the 85 along with a T56... The 88 is still up in the air, will be stock for a long while, I just got it last week...

 

Clutch fan or electric? I'd always have a belt squeel when only running crank/waterpump/alt with the clutch fan. There wasn't enough surface area on the waterpump pulley for the belt. I switched over to an electric fan setup and got rid of the squeel. Next problem I had was the belt flying off at higher rpms with the new engine. Solved that by putting, I think, a 36 inch belt around the crank and waterpump pulley along with the other one that goes to the alt. Hasn't given me any problems since and has stayed on till at least 7400 rpms