[Schroeder]

It annoys the hell out of me. I have stock belt setup on an AC 77 TA with a 461 stroker. They squealed before the stroker too. Today one popped off, got shredded by the fan, and made the other pop off. Car WAY overheated. No smoke. Stopped 2-3mins after fan and water pump stopped. Would u guys be worried? What the hell so I have to do to stop the slipping. No matter how tight I get the belts they slip if sudden gas is applied. Are upgraded belts available? I cant believe they were like this from the factory, so dont tell me I have to get a serpentine setup or one of those tredded belt setups ad change all my pullies because I will call BS. Thanks in advance

[indymanjoe]

Power steering belt is supposed to be wider than the alt belt.Most replacements are the same width.Went through this last summer on mine.

[rohrt]

I use a 15mm and 17mm on my car. Works great.

[BLANK1]

Had that problem too. Was using Gates belts then switched to Dayco cogged style belts and no problems since.

[PontGuy]

X2 on the wider power steering belt. If you look at the pulleys you will see the grooves are not the same width. And the belts need to ride at the same height. I have no idea why all the catalogs specify the same width belts but I learned this a long time ago.

Also use good high-quality belts, clean pulleys with no paint, oil or dressing on them. And make sure the pulleys line up properly. Spacers were used on PS pump mounts to get them lined up and these are often missing.

[Grand73Am]

Also, there are belt tension specs in the factory Pontiac service manual for your car. For example in the 78 Pontiac service manual, the tension specs are section 6B, Engine cooling, Accessory drive belts.
Many times, even though you think you have the belts tight, they still aren't as tight as they should be. A V-belt tension gauge is needed to be able to accurately measure the tension as you're tightening them to factory specs. I got my gauge from NAPA. They don't cost much, maybe $15, and can be found at other places.
Before I got a gauge, I thought I had the belts tight enough, but was surprised to find I had to tighten them further to meet the specs.
Here's a good tutorial on the use of a belt tension gauge: https://www.youtube.com/watch?v=z11wfc-0-hY

[firechickenman]

Sounds like your pulleys are out of line. Sometimes it's hard to see. With the belts off, take some straight tubing (something alone the lines of an aluminum arrow or 3/8" fuel line) and put it in the crank pulley groove. Hold it tight in that groove and rotate it to other pulleys. You should see what's out of line.

[Chris65LeMans]

Yeah - definitely sounds like an alignment problem to me.

[tripwr1964]

2x on the dayco belts.
also once they come off, throw them away and get a new one.
once all is meticulously aligned, a belt tensioner helped me to get a feel for proper tension.

[tripwr1964]

2x on the dayco belts.
also once they come off, throw them away and get a new one.
once all is meticulously aligned, a belt tensioner helped me to get a feel for proper tension.

[Schroeder]

Dayco? Does oreilys have these? Does anyone have specific part numbers of these 15mm and 17mm belts so I get the proper lengths? I went up to Oreilys THREE times yesterday. I'm tired of running back and forth.

I have the factory spacers in place and the pulleys appear to line up, but yes, that is just visual.

[PontGuy]

I just put Dayco Top Cogs on my TA a few months ago. The previous owner had same width cheap belts on it and as expected they squealed. I agree with everyone else here the Daycos are the best. I bought them from Advance- the sizes stocked were limited but they were able to get ones the correct length next day.

For my 74 with factory brackets and pulleys I used 15485 for the alternator and 17515 for the PS belt. Don't know if the lengths will be right for your 77, but should be close.

[Schroeder]

U can buy the pulleys that will fit on the OEM pumps and alternators? Do u have those part numbers? Although I'd like to try just the belts first and c if that solves the problem.

Ill look those part numbers up and make sure theyre the right lengths for my car. These cogged belts will work with standard pulleys though?

[indymanjoe]

the first two numbers are the width's.I believe the rest is length.

[PontGuy]

Are you using original factory pulleys? If not that could be another issue- mixing and matching can cause problems. I haven't had to chase down pulleys for a long time but based on threads posted here during the past few years getting the correct parts can be a bit of an adventure.

Yes the Dayco TopCogs are designed to work with factory pulleys. If you have original pulleys then the catalog lengths may match your car correctly, but for some reason most of the chain parts stores list the same width for both belts even though that is wrong. (Yes the first two numbers are width in mm and the last three numbers are length.)

The pic I posted earlier shows them on my Lemans engine. As mentioned I just installed a pair on the TA a few months ago. Absolutely no squealing on either.

[Schroeder]

Im assuming that the length is in millimeters too? So a 49.25" long pulley at 15mm wide would be the dayco part number 151251? How about those top cog part numbers tho?

Also, I am using original pulleys.

Will the belts alone on standard pulleys be a big improvement for me without the cogs?

[gtofreek]

The last three numbers are the length in inch's. For example; if the part number is 15515, then the belt is 15MM wide, and 51.5 inch's long. A 15510 would be 51 inch's long.

Also, is your fan bolted to a fan clutch? Or did you bolt it directly to the water pump? If you look at the water pump pulley, the belt makes contact for a very short distance. Maybe 25% of the pulley. There is not enough surface area for the belt to grip if running the fan without a clutch. This causes the belt to slip under acceleration. Then the belt gets to flopping around until it pops off.

[gtofreek]

The last three numbers are the length in inch's. For example; if the part number is 15515, then the belt is 15MM wide, and 51.5 inch's long. A 15510 would be 51 inch's long.

Also, is your fan bolted to a fan clutch? Or did you bolt it directly to the water pump? If you look at the water pump pulley, the belt makes contact for a very short distance. Maybe 25% of the pulley. There is not enough surface area for the belt to grip if running the fan without a clutch. This causes the belt to slip under acceleration. Then the belt gets to flopping around until it pops off.

[gtofreek]

These forums are all screwed up since the change to maxperformanceinc. All kinds of posting and PM errors.

[Schroeder]

I thinki have some measurements, but again, does anyone have exact part numbers?

I have a the fan bolted to the clutch. Thats bolted to the water pump pulley.

Did u try sending me a PM or something?