[Ironhorse]

If you have access to one I've had good luck running rubber snubbers, seals or bumpers or cushions, what ever one wants to call them, thru my glass bead cabinet. I normally blast cast iron and steel parts at about 80 psi. When I do small rubber parts I turn the pressure regulator down to about 40 psi. They come out looking almost like new.

The Dawn dish soap and water soak seems like a good try also. Maybe after the bead blast to open the rubber pores.