[jpinkert]

I have yet to find anything definitive about piston angles (the standard 20 deg) on the 930 calipers, but mine have been noisey for about a year since I replaced the rotors and pads.

So I pulled the pads on one of the front brakes today and found that the leading piston on one side was at about 20 degrees, while the other pistons were all vertical.

I did some searches here and on Pelican and found:
http://forums.pelicanparts.com/showt...threadid=90849
and
http://vintagebus.com/howto/brakes/rebuild/ (pics of rebuild manuals)

Also, if I want to turn a piston, what's the best way to do it without damaging them?

[scphelps1]

Hi Josh

Check this link. http://forums.pelicanparts.com/showt...caliper+piston

To say that mine were LOUD after the rebuild is a severe understatement! It turns out the pistons were a full 180 degrees off. With the 930 pistons they don't have to be turned 20 degrees to the edge of the caliper (should be perpendicular to the edge of the caliper), but they do have to be oriented so that the lower portion of the stepped piston is facing the incoming rotor.

To rotate them, if necessary, I would recommend blowing them out. Use a block of wood inbetween them so they don't crash into one another.

[jpinkert]

Thanks for the tips. There's got to be some way to turn the pistons without removing them completely. The last thing I want to do is have to blow air in there and then have to flush them out. I'm going to try extending the pistons a little with the pads out (and a block of wood in there), then putting a hose clamp around them with a shop rag or paper towel underneath (to prevent marring).