I took mine apart and cleaned everything. I sealed it back up with silicone. It seems like I used teflon plumbers tape, the kind you use to seal the threads on pipes, to seal the area that the paddle pivots from. I lubed the sealing surface of the paddle with a little silicone grease. I am sure this shouldn't work but my wipers move just fine. They couldn't swing far enough to make the valve change direction because the crud in the paddle chamber was limiting the travel. If you kill it send it off for repair. I used a small wrench on the screws. I do plan to replace it at some time with an electric motor. Even new the vacuum wipers were crap.
