On mine the oulet is perpendicular to the axle so it makes no difference which way you spin it however it runs better one way and I think that has to do with wear on the gears. Taking it apart now that I have done it a few times is easy, it's only six screws\bolts and four gears. I took it apart yesterday afternoon but apparently my reply didn't post (spotty internet in the middle of nowhere) there was some play in the bushings so I greases them all and my tests so far have run smooth, however I did not do an extensive test, that will likely be Saturday.