I need help in a bad way. I have a john deere 647 quick trac mower. The right hydro gear was sticking so I took it apart and cleaned it. When putting it back together I ended up pushing the stem through the bottom of the gear case. So I pulled the unit and replaced it with another hydro gear I pulled off my parts mower. I only had a left gear left on that one so I turned 180 degrees and hooked everything back up (left the original head from the broken unit on since it seems ok). The mower runs fine if its on a flat surface but it seems to loose power on the right side if I try to go up an incline. I'm not sure why it's doing this. Any suggestions on what to try next would be greatly appreciated.