Squeaking Drive Belt VS V6 commodore

[Changa]

Ok so my engine belt is squeaking, now before you say replace the belt I have gone through three belts already, all doing the same thing. I thought the belt was slipping so I put some belt grip onto the pulleys, its only got worse. So I am guessing the belt is actually gripping too much because when I lubricate the belt and pulleys the noise disappears. This only fixes it short term though because as soon as the belt dries out it starts to squeak again. By the way I had a mechanic look at it and they looked at every pulley replacing the bearings in the suspisious ones. Heard someone say while I was there (another mechanic) that he had been having alot of trouble with squeaking belts like they had changed the compound used for making the belts. I am currently using the repco brand of drive belt called dayco, the first belt that started squeaking was a gates racing belt, so the squeaking isnt confined to one brand of belt. Just wondering if there is a way to keep the belt 'supple' and 'moist', by some form of lubrication that doesnt have to be applied like every day, like some kind of grease that doesnt just melt and drip off.

 

[tt460]

sounds like a bearing, try spraying 1 bearing at a time with wd40 and find what bearing is making the noise.

could also be be slipping on a pulley and the pulley needs roughing up with some sandpaper to help it grip.

 

[Changa]

As I said before the mechanics looked at all the bearings and pulleys for the problem and replaced any dodgey ones and it still squeaks. The thing is, I dont think its slipping, because I put some belt grip stuff on there and it just made it 10 times worse. But when I put on some silicon spray (lubricant) onto the belt and pulley ribs the noise disappears. Its almost like it grips too much and makes a noise and when lubed it stops it.

 

[tt460]

Just try what i said with spraying the bearing on the pulleys one at a time. it will take 10 mins max and you already have silcone spray so its not going to cost anything.

 

[Changa]

Lol yeah I have done what you said about 8 times before, it doesnt really help at all. It does stop the squeaking but only coz the lubricant drips onto the belt making it moister and more supple. Its like the belt grips too much and needs to be lubed.

 

[88GreenVN]

Run some candle on the belt while running the car. Worked for me on my VS.

 

[Changa]

Yeah the noise seems to have gone for 2 days after spraying that silicon spray on the belt and the pulleys.

 

[Nadroj]

Squeal fix

Harking back to the days before German designed Holdens, there was a model (forget which) with a Red straight six motor that also had a common fault of squealing belt - the fanbelt as it was called those days.
The cause was a pulley that hadn't been machined deeply enough, so that the belt would often ride on the bottom of the Vee, rather than on the sides. That led to slip and noise. The fix was to remove the offending pulley and machine the Vee deeper on a lathe.
So, could this fix be applied to a Commodore's serpentine belt? It has many small Vees, but essentially it is still a V-belt. The belt could still feasibly ride on the bottom of the grooved Vees on a pulley, especially if it was worn. But, machining several grooves wouldn't be so easy as with the single Vee pulley. So, rather than deepen the pulley grooves, I removed a small amount of rubber from the tips of the belt itself. Method: Stapled a strip of abrasive cloth to a piece of flat timber, and with the engine idling, rubbed it in a position where it was going over an idler pulley, ribbed side out. A minute or so of this treatment, and 4 days later still no squeaks. Wunderbar!
Jordan

 

[hako]

Serpentine belts do not rely on "Vees" to grip as they do not have "Vees" like the old "V" belts...instead they have ribs with straight edges which increase the surface area of the belt in contact with the pulley improving grip plus they are designed to wrap around the pulley.
It's possible for squeaking to occur when the ribbed pulley is not in perfect alignment with the serpentine belt...this can be checked by placing a flat ruler/edge against the front edge of the pulley and checking that it runs in the same plane as the belt.

 

[Nadroj]

Serpentine belt info

Where are you getting this information, hako? It's not correct.
Multi-ribbed belts have the same angled sides as single Vee belts - 40 degrees included angle. I dare say an old single Vee belt is also designed to wrap around a pulley!
See picture of some multi-vee pulleys that I made for an old bike. I used the info on the table to make them. You can also check Machinery's Handbook for detailed specs.
Jordan