mikex7

So I have an obnoxious squeal on load and my local shop diagnosed my tensioner needing replacement. Easy enough, but since Ill be down there I also want to swap the belt for a gatorback and change the idler pulley. First time doing this on a vette but you gotta learn somehow. I found this write up which seems easy enough: http://www.superchevy.com/how-to/cor...-belt-install/

Ive been trying to find an idler pulley to buy and each one says its the A/C idler pulley. Is that the same thing? Excuse my ignorance. This is the part I found that looks identical to the pulley referenced in the link above: http://www.ebay.com/itm/like/371138679635?lpid=82&chn=ps
If I buy that idler pulley, the tensioner, and the belt, should I be good to go?


Alright.. according to this image there are two:. Is #38240 for the main drive belt or 38241?

HBsurfer

This is the C6 forum but everything you posted is for a C5. What is your car?

HBsurfer

I'll assume you have a C6 so the diagram you posted would be slightly different. Here is what you have on a C6. If you have a C5 you should ask the question on that forum. Hope this helps.

Dano523

Two belt tensioner's with ball bearing wheel pulleys (one on the main belt, and the other on the AC belt), and then two idle pulleys with ball bearing inside it for a count of four ball bearings that may need to be serviced.

As to add, you can pull the pulley wheels with bearings, pull the side seals to clean the ball bearings themselves, then repack the ball bearings and put the side seals back on before reinstalling the ball bearing pulley wheels.

The OEM bearings are under greased to begin with, and this and over time, what little grease is used to lube them dries out.

I bring this up, since no reason to throw the baby out with the bath water when the tensioner's spring loaded sections are still fine, and it just the bearings on the wheel pulleys that need to be cleaned and re-greased instead.

scotzz

Any special tools required to replace the belts? (I have a C6)

schpenxel

No. Socket or wrench and thats it (to loosen tensioner)

Two tensioners, one idler. One tensioner for main belt, one tensioner for AC belt. Idler on main belt.

Dano523

To add, most the time the bearings are fine, but the grease in them has dried out instead.

So just pulling the tensioner/idler bearing to clean and re-grease them fixes the problem without having to spend any money on new bearings.

schpenxel

Very good to know! I was about to replace these on my truck

scotzz

Are the tensioners spring loaded? If not, how do you set tension? Also, can you replace both belts from the top or, do you need underside access?

Thanks, Scott

schpenxel

Yeah, they are spring loaded

They have a nut on them that you can put a socket on and use that to remove tension from the belt

Main one can be done from up top. Not sure about the AC one though.. probably possible but I've never done it from top only

Here's what one of them looks like. Put a socket on the "nut" in the center of the pulley and then you can remove tension from the belt with a ratchet (or wrench, whatever you prefer)

Joe_G

I agree thanks Dano523! I wasted money replacing my idler...I still have the old one in my garage, wish I'd have known I could just grease it....

HOXXOH

Since the OP's is squealing, the ***** and/or races have already seen scored and no amount of grease will fix that. Just putting everyday grease in a bearing may give it a little more life, but that's false economy, since the bearing itself has already been compromised before you contaminate it with a non-compatible lubricant. You'll just have to repeat the labor rather quickly. The bearing is a deep grooved design to give it thrust stability. It'll still function radially after the sides of the races have worn out, but it'll wobble and grease won't fix that either. The rotational design speed is around 12-13K RPM, so life is shortened by those who go near redline frequently. The use of a non-compatible lubricant will affect the design speed.

You can check the bearing condition by removing the main belt from the tensioner pulley and feeling for the amount of wobble. If you can easily feel play, that bearing and the other 3 are already on their last legs. Yes, they'll last for around 100K miles of normal operation and take even longer to die completely, but they also start putting abnormal wear on the belt, which would then need replaced.

The bearing itself is a 6203-2RS made by GBC. This is a standard bearing and made by several different companies. They sell on ebay for as little as $2.62 each. Since the engine uses 4, you might as well get all 4 for $8.79 shipped and replace them all at the same time.

There is also a significant downside to replacing the bearings and that is the removal and installation. The pulley was designed to allow a snap in press fit with the retainer being a flexed function of the pulley itself. The integral retainer must be ground off on one side and then the old bearing pressed out. The pulley will need cleaned and an adhesive applied to the interior surfaces before the new bearing is pressed into place. Some people may not understand the construction or have the ability to change the bearing, so this is not for everybody. Of course, it may be fun to try, since the bad one will still be junk if you mess up, or $3 if you fix it. The GM part for the complete upper tensioner (12569301) is about $70 online.

The far better deal that requires no skill other than swapping parts, is to buy just a new pulley with the bearing already installed. Several brands (probably all the same manufacturer) are on Amazon ranging from $10 to $17.

Joe_G

Mine would squeal when cold but shut up after about running for 15 minutes. Tom you think that is shot?

I may pull it apart to take a look, but I don't have a press. I do have a vise, (me? I have no vice, I'm as pure as the driven snow...yea...but you drifted) so maybe I could figure out a way with that and some sockets.

Tom I think us old guys will recognize the quote....

HOXXOH

By the time they make any noise whatsoever, bearings are history. The really huge and expensive ones are worth repairing, but anything less than around $5,000 are throwaways. Bushings, however are a different animal.
I've seen roller bearings with an ID of about 20' and the rollers were about 10" diameter and 3' long. I wish I could have seen the equipment that made it and the shaft it went on.

If you want to try removing the bearing just for fun, remember that the OD is 40mm and you can't just press it out of the pulley without grinding away the integral retainer. This is not like the old days when manufacturers used snap rings on car parts.