I'm in the process of refitting my supercharger pulley and have the supercharger belt removed. I noticed that the idler pulley (the stationary one, not the tensioner) has around 1-2mm of side to side play if twisted from the pulley edges and when turned freely it sounds like you can hear the ball bearings sloshing around a bit, though it turns very freely.

I have never noticed any noise when the car was actually running. Does the idler bearing need replacement?

 

Yes they do, not sure what their max life is though. You can put in a new bearing easily, they cost just a couple of dollars. Should be easy to find, I used some SKF ones, but can't remember the partno.

 

Very easy to change just take the old bearing to any supplier and they will be able to supply the same or equivalent

 

Thanks guys. I pressed the bearing out an measured it with calipers. This looks like and exact match:
http://www.grainger.com/Grainger/wwg...N=0&sst=subset

It is less than half the cost of repacing the idler pulley/bearing assembly from Jaguar.

 

Mine had play aswell. I went to a local parts/machine shop and they pressed in new bearings on all my pulleys..about $25 ea for parts and labor. Get good quality bearings...not made in China. I can give you the part numbers if needed.

 

I would stay clear of the Chinese/Taiwan bearings, they are not a very good standard/quality, try and source something more home grown even if it does cost you a few $$ more

 

Ten+ years later... this thread just saved me on my quest to replace the supercharger idler pulley -- which turns out now to be a very difficult part to locate. The Grainger link still works, the part is still available in 2021, and it's an exact match for the bearing I need to replace. Thank you WhiteXKR !

 

Just search for 6303-2RS. SKF, KOYO, Timken and other manufactures use the same part.no. It is a standard one row ball bearing with outside diameter 47 mm, inside diameter 17 mm and with 14 mm.
2RS means it is sealed on both side with rubber. You can also use 6303-2Z that means it is sealed on both side with steel.

 

Amazon also has the above bearing #’s. They have them from several different manufacturers, I would suggest the Timken product.


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