Originally Posted by G-REX
Caddy, third picture down - do you think your rotor assembly is rubbing the cover plate and maybe causing drag or even stopping the vanes from moving? Mine didn't have that many scratches on it when I took it out. It was almost completely smooth like fresh out of the lathe. I say almost because there was one scuff on the ring.
Good eye there.
I only handle the rotor and internal parts with my clean hands or a terry cloth towel. After I pull the pump off I wash it the exterior and my hands before cracking the thing open. But scratches I see on the cylinder wall are from the variable displacement of the pump itself. It rocks left to right on the little pivot pin. Don't know why they're on the rotor.
If the rotor and the vanes were scraping the cover plate on the back of the pump you'd expect to see the round scratches centered around the shaft. You can actually see a little bit of those if you look at the tips of the vanes.
My pump is back together again, pumping fluid. As soon as I get all the air out I'll give it a test on the section of highway that was causing my shuttering.