Write-Up: Replacing Belts and Pulleys

Tonight-tonight...you're driving again.

When it pours it.....snows. ...apparently

Haha...so I take it..... you're drivin

Well I got off work at 4 to fix it. Autozone twice gave me the wrong size belt. Don't know how. I ended up looking it up myself and going in with the correct part number. I didn't get done till like 8 last night. Ended up running out of daylight and working in the dark. It's fixed now though and running great again. Now to get that body fixed.

Without reading all 17 pages of this topic and assuming no one else posted this already I found the Duralast part number for the lower 3.5" pulley, This is a metal pulley to upgrade from the plastic one:


I got this pulley through Autozone for $17.99. This pulley will not pull up when doing an application search and they could not find it when looking on their system, however they were able to find it in the back.

Is that the one that's 3" stock? I need to get a 3.5" soon, planning on dropping another size when I get my DP.

No that one is 3.5" ( 90mm ) stock. The one right above it is 3" stock and the 3.5" can be used with a 3.4" SC pulley while using the stock belt to gain more wrap on the SC pulley.

Ok, that's what I was thinking of. So the 3.5 you got will work on the 3 then?

I'm not 100% sure they have the same inside diameter on the bearing, maybe someone can chime in. however ZZP sells that upper pulley in a 3.5"

Sorry if this was addressed in the thread already, but is there any easy way to get to that idler pulley on the main belt? The one that's hiding behind the motor mount and seems like it would be impossible to get at?

Thanks!

Sir Psycho Sexy wrote:

Sorry if this was addressed in the thread already, but is there any easy way to get to that idler pulley on the main belt? The one that's hiding behind the motor mount and seems like it would be impossible to get at?

Thanks!

Nope. Giant bracket needs to be removed. No shortcuts for that one...

Abaddon wrote:

Sir Psycho Sexy wrote:

Sorry if this was addressed in the thread already, but is there any easy way to get to that idler pulley on the main belt? The one that's hiding behind the motor mount and seems like it would be impossible to get at?

Thanks!

Nope. Giant bracket needs to be removed. No shortcuts for that one...

Yayyyy

*Cough*95 for the win!*Cough*   

I don't think this has been asked, but can you use the 3.5" oversized idler pulley (the one that is normally 3") with a 3.5" supercharger pulley? Mine is making noise and grinds when spun by hand. It's ready to go any minute so no matter what I will be replacing it tomorrow. I would just like to get the bigger one in case I ever drop another pulley size.

I know the Series II has a much MUCH different belt arrangement, but I did just that on my Series I. I dropped from a 2.8" to a 2.5" and there's no ill effects. I can't see it being much of a problem, just watch for clearances with your engine mount in that area.

matt270avian wrote:

I don't think this has been asked, but can you use the 3.5" oversized idler pulley (the one that is normally 3") with a 3.5" supercharger pulley? Mine is making noise and grinds when spun by hand. It's ready to go any minute so no matter what I will be replacing it tomorrow. I would just like to get the bigger one in case I ever drop another pulley size.

Probably too late, but yes I did this.

I've looked through several threads and google searches and cannot locate the part # for the SC 3.5" tensioner pulley.
Does anyone have it handy, please?
Thank you

charlieRobinson wrote:

I've looked through several threads and google searches and cannot locate the part # for the SC 3.5" tensioner pulley.
Does anyone have it handy, please?
Thank you

try old GM p/n 24506756 for the steel sc idler pulley. old Delco# 15-4683

Pulley on tensioner try old GM pn 24502989 this is the one grooved to front of belt. Don't have a Delco # for it sorry.

Albertj

Thanks, Al. Stock SC tension is 3" I want to move up to a 3.5" tensioner to hold my belt tight around the 3.25" SC pulley

Today I changed the S/C belt tensioner pulley hoping that was the source of the noise I could hear from under the hood. Installation was easy, but I never realized until rereading the OP that there were marks that had to be lined up. What exactly are they supposed to be lined up with? I can't really tell in the pictures, or on my car.



The belt kind of moves side-to-side on the S/C belt tensioner pulley. It also kind of "jumps". I don't literally mean jumps, but you can see it moving up and down too. Maybe I need a new belt too? I'm not sure.

Make sure you have the belt aligned correctly with the bottom grooves of the crank pulley.

AA wrote:

Make sure you have the belt aligned correctly with the bottom grooves of the crank pulley.

Do I just feel for this?

You can if you know what to feel for, or you can look under from the front.

AA wrote:

You can if you know what to feel for, or you can look under from the front.

Aside from part of the belt not being in one of the grooves, I don't think I know what else to look for. I had this thought that maybe It's because of the new S/C belt tensioner pulley being new. The old one had the black worn off from where the belt had been riding on, but the new pulley doesn't. That's probably a really ignorant thought, but that's all I can think of. I don't know how that would cause the side-to-side and up and down action of the belt.

Ugh, need the S/C idler pulley that's surrounded by the engine mount.