We used Webb's pulley puller with the 13mm negative ground bolt in the SC shaft.

We installed the CS pulley and were torquing to their specs, when a bolt snapped. It wasn't until we removed the CS pulley that this piece was visible. At that time, it was just hanging on the SC shaft.

 

Well then sounds like you did it right on pulling the OEM pulley off.
Torque in inch pounds or foot pounds?
From looking at your pictures and the design of the CS pulley it doesn’t look like the mystery part is from that. I only have personal experience with Helix13 pulleys, two piece six screws.
Maybe someone here that has pulled a supercharger apart could tell.
My bet is on front shaft seal/bearing retainer though.

 

Their instructions said ft-lbs, will be changed to inch-lbs. I had a second pulley available, that was for someone else. We used that one after removing the first CS pulley. They are replacing the pulley.

The mystery part is not from the stock or CS pulley. I'm guessing that the over torquing of the bolts dislodged this piece.

Since it has been removed, does anyone know of any long term risks associated with running without it? BMW/MINI does not sell the part.

 

WOW 7mm! That takes some doing!

I have seen this many times before, and also the opposited where someone hits the end of the shaft to get the pulley to go on.
My experience is that you can carefully tap the Shaft back into the SC and everything will be fine. Whatever is in the SC(bearings, spacers, and blades) will move until it hits the other side, and the shaft will then start moving.

Ya, i thought 20ft-lbs seemed a bit high!

I am very sorry for your problems, but i think they are fixable without too much trouble. But i would for sure talk to the shop that installed the pulley before going too much further. Make sure they did remove it by using pry bars. If they used the correct tool, you might have other issues.

 

I did the install myself. I just finished the pulley install for the third time on Friday. We were able to get a new retainer ring, and get it seated. Everything is working fine.

Then, we did a pulley on another local club member's car.

After four of these, I'm getting pretty good at this.

 

*TOUCH WOOD*!! same here no problems as of yet but i'll keep an extra eye out! thansk for the info

 

Here's an odd one.


In order to reach the lower pinch bolt the hub sits too high on the shaft. I would suspect the shaft is too short but this SC had an Alta V1 for 30,000 miles with no belt alignment issues.

 

We had to do the same thing to my pulley alta v2.0. My car was factory before the pulley and when we went to put it on the hub went too far down on the shaft. The inner most set screw was not accessible because of the flange on the sc housing being too large. Hard to explain but what was happening was the hub was almost burying itself into and around the sc housing. So we had to pull it back out a little bit just till the second set screw was accesible and then tighted everything up and and no problems. I've had it on about 3000 miles and no issues so far.

Steve

 

It seems like this is going make it more difficult to know when the SC pulley is properly aligned. Did the SC design change at some point

 

The amount of room we have in order to get the pinch bolt spaced out makes for a tight clearance on the body of the SC. But a normal wrench (the one we supply) can get to it, as will a ball end type.
Yes the wrench may barely touch the body, but not enough to interfere with tightening. But too much deeper than the above pic and that is not normal. Maybe the SC shaft go pushed in???

 

I have installed 4 V2 pulleys and have also noticed that the bottom allen screw sits so low that it is dififcut to get too. However, I played with some different kits and finally found an extended allen key (socket style) that would allow us to get in on a slight angle. This will throw the torque off but we did the best we could with what we had. No problems with any of them to date. (several months running).

I also keep a rubber mallet on hand to aid in tapping the hub down to get it seated.