Everything about this Cup car is new to me and that includes servicing the 3 piece BBS wheel. My Cup car came with 3 sets of BBS wheels and one rear wheel had a bend outer rim and one front wheel has a slow leak. It was easy to take them apart but ... how do I seal them back up to prevent future leak? Replace the O-ring with rubber seal vs just applying some sort of silicon sealant?

I did bunch of research and looks like alot of folks don't bother to replace the sealing rubber O-ring from BBS since they fail with time and just apply silicon sealant along the exposed seam. Some suggested Dow Corning 832 silicon sealant:
http://www.bdi-usa.com/DidYouKnow/Do...spx?Print=true



I could not find the replacement BBS sealing O-ring any where. I think it is an exclusive Porsche motorsports parts as shown by #4 on the following diagram



Here is what the wheels look like. Bend outer rim on the rear wheel and slow leak from the one of the front wheel



The rubber seal on the rear wheel is exposed vs concealed set up for the front wheel





The replacement outer rim for the rear wheel



The 20+ bolts required a 12 points 8 mm socket which was hard to find



Here is what the sealing O-ring look like



Everything apart



Anyone has a good suggestion on how to get rid of caked on tire rubber??

 

Yes, you are correct about sealing the wheels and the Dow Corning 832 sleant is a good choice. Takes a good 24hrs to cure, so wait to mount a tire. Use electrical tape to mask both rims to get a nice line. Use a curved putty knife to scrap off the excess sealant or a wet finger to smooth out the sealant. Before putting the wheel back together clean the rims. The two surfaces clean with Scotch-Brite and then Acetone so that the sealant will adhere to both surfaces.

Looks like your wheels need a good cleaning and check the torque on all the bolts and the valve stems or just replace all the stems and bolts.

If you need any assistance contact Rob @ S-Car-Go Racing in San Rafael. They have quite a bit of experience with repairing 3-piece wheels. www.scargoracing.com

Good Luck!

 

New seal from BBS my friend! You won't get any leak for a while. Leaks come from tires also, make sure they are perfect.