Philly89Iroc

I don't understand it but the v-belt for my alternator keeps getting loose and starts squealing whenever the car is first started, sometimes under hard acceleration, and if it gets wet (rain, humidity, etc). I've tried different belts (dayco, drive-rite, Goodyear, and now currently a high quality NAPA belt on the car), belt dressing, changing the top alternator bracket bolt/washer, roughing up the pullies with sand paper basically to no avail. The belt is as tight as it will go and it still does it, plus I've tried re-tightening when the car is very hot or very cold, makes no difference whatsoever. Often, I have to re-tighten it after several days/miles of use, which solves the problem only momentarily. The alternator on the car is brand new (Delco unit) and the alternator that was on the car was a working Delco unit (circa 2000), just the pulley did not look so good, so I thought a new alternator would solve this problem.

Now its at the point where I have it where it generally doesn't squeal on start-up but sometimes it still does it at random re-starts or when driving. It just makes it sound like a complete pos to the point where I feel embarrassed to own the car and its already broken one alternator belt because of this issue.

I really have no idea how to easily fix this since I'm used to a reliable serpentine belt setup. Maybe I need some special tool to stretch the belt or the alternator? I really don't want to change water pumps or go to great lengths to change to a serpentine belt if that is the only solution, but if it can be done easily I'll try it. Any suggestions are welcome and I'd prefer to keep the stock setup if possible. Thanks for the help.

The car is a 1982 MSE Trans AM with a 305 LG4, stock belt routing, smog pump still in place including correct brackets, etc. The belt routing has not been changed or modified in any way and all other belts work properly.

RED86Z28

Is the belt wearing on one side more than the other? Even though everything is stock you could still have a slight pulley alignment issue. Alignment problems tend to wear belts quickly.

Philly89Iroc

The belt seems to look normal but I'll check it again, it doesn't show much wear since it was replaced less than three weeks ago. The last belt broke (500 miles on it lol) because the shifter jammed and it jumped off the pulley. I noticed that it sits tight in the pulley (no gaps), but if I push the fan blades of the alternator, I can move them slightly downward with the belt on the pulley. When it tightened again correctly, there is no movement but it still works itself loose eventually to the point where I can do the same thing again.

camaronewbie

Are you tightening both alternator bolts? You tighten the belt by swiveling the alternator on the main bolt, them tighten the slide bolt, then tighten the main bolt. If you aren't tightening that main bolt, I could see where it could come loose again in a few days.

Philly89Iroc

Yep, I'm tightening both alternator bolts in exactly that order and I tried tightening it in the reverse order as well. Is there some tool to stretch the belt further or maybe do I need to put the belt on the alternator first then wrap it around the crank pulley? Generally, I put the belt around the crank pulley first then on the alternator and pull the alternator left (towards passenger side) as far as it can go. Thanks for the help.

Philly89Iroc

Well, now its about to kill the third belt I've put on the car in less than 1,000 miles. Its worn the belt inwards towards the middle on both sides of the belt almost forming a point and squeals every single time its started now. Are there any solutions to this problem? I'm installing the belt correctly and the pulleys work fine as far as I can tell. Could I maybe swap out the alternator pulley for something different or try a different belt size? The odd thing is I had the second belt installed by a third gen mechanic. It worked great for a short time then started having the same issue again until it finally broke. All other belts function flawlessly even the smog pump belt.

92RS_Ttop

iTrader: (3)

I've been fighting the exact same issue myself. I'm on my third belt this summer. I have tried everything you have and got the same results. I'm thinking mine is an alignment issue even though everything looks like its lined up right. Mine tends to "shave" the belt as I've got rubber dust coating my water pump after a week or so with a new one.

I use an 18" pry bar to stretch the belt when I tighten the bolts. It's to the point where I'm going to switch to a serpentine setup. I just need to get the belt and pulley for the power steering pump. I'd prefer to keep the V-belt setup so I'll be watching to see if you find a solution that works.

w00dr0w

Has anyone figured this out? My 82 Z28 is breaking belts about every 500 miles.... There are a few suggestions on here I haven't tried yet, but it would be nice to know what actually works!

8t2 z-chev

make sure the correct pulleys are in place-'82-early'85
v8s with A/C have a crank pulley with 3 grooves of the
same size and the waterpump pulley has the two rear
grooves of the same size+the front smaller groove for
the smog pump-these pulleys were used on '76-early
'85 chevys with the R4 compressor.
For '69-'81 with the A-6 compressor,the crank pulley
has 1 large front groove and 2 smaller rear grooves
while the water pump pulley has a large front groove
and a smaller rear one-if these pulleys get mixed from
one style to the other,massive belt wear and squealing
will result
If the correct pulleys are worn uneven you might also
get rapid wear...
BTW,'82-early '85 v-belt v-8 thirds with high-
performance engines;LU5,L69,LB9 ETC.got special
deep groove alternator and A/C pulleys to help keep
the belt in place at high RPM

Humph7ey

I had a similar problem on my '82 V8. The belt kept jumping itself upside down and wearing out.
Turns out that the previous owner who was NOT a mechanic had the crank pulley that has two grooves had the back one correctly driving the water pump and the steering pump.
The trouble was that the front one was driving the alternator using the water pump pulley as an idler. The water pump pulley was literally grinding down the belt.
I have just ordered a short belt that should use the water pump pulley as the driver for the alternator.
Just make sure that the belts have an un interrupted path and are not using a pulley that is running at a different speed.
The car did have air conditioning so I may be quite wrong.
I will try for some pictures later.

Ice cold spit

I had this same issue thought it was something wrong with the altenator bought a new one same issue with the belt tight then thought now its got to be the water pump had another friend stop by for a fresh set of eyes ended up being my power steering pump bolts were backing out putting the pump out of line so don't be so sure the problem lies where you think try and check everything good luck!

Humph7ey

Here is the way it looks and what I propose to do.

hellz_wings

iTrader: (2)

What is the torque spec for the bolts that bolt up the alternator to the bracket? (the upper front one and the lower front ones are what I loosened in order to remove the belt). I'm going to put the new one on and want it to be tight so it doesn't loosen (For the tension: I've heard that as long as there is 1/2" of slack, that's how much tension there should be).

Jonesyfxr

iTrader: (2)

I use a 3' breaker bar to tighten our drag alternator belts. We never have an issue with them squealing or flying off. We also use a straight edge along the leading edges of the pullies to make sure they are in perfect alignment.

sofakingdom

iTrader: (1)

"Proposed" won't work. It's WRONG.

"Wrong" is correctly labeled: it's ALSO WRONG.

"Correct" is not shown. It would have the alt going over the crank and WP, with the belt in the outermost LARGE DIA groove of the pulley. The SMALL DIA groove in the WP is for the AIR pump.

Just assemble it correctly, and then learn to tighten the alt/WP belt properly. That's all you need. Not really rocket science or anything.

Personally I use a tire tool and catch it on the side of the head underneath the alt - NOT the valve cover.

Not sure what all this "reliable" talk is about; V-belts worked fine for the rest of us for A LONG LONG TIME, before the accessories on the front of motors became so standardized (i.e. all cars had PS, all cars had AC) that it was economically practical at the factory level to create a "one size fits all" belt. Granted the serpentine design is definitely "better", but that's a long way from dismissing the older system as "inadequate".

Torque, as always with all hardware in every application everywhere on every part of every car and everything else, goes with the hardware size. For the size of bolts used in those 2 places, correct torque is around 22 - 25 ft-lbs on the adjustment bolt (either 5/16" or 8mm depending on whether you have the "metric" or "standard" bolt), and around 30 ft-lbs on the pivot nut (3/8").

hellz_wings

iTrader: (2)

Jones: I think the pulleys are all aligned and the belt is just old (it's going on 7 years now that I own the car and never changed it o_O )

Sofa: Thx, I'll use those tq specs. Just to be sure, the adjustment bolt is the one at the top that is slotted right? And the pivot nut is the lower one? (both bolts being on the front of the alternator). thnx in advance