Hi there guys, new to this forum hoping somebody can help. My 751c has nearly lost all drive to the right hydrostatic when reverse direction is selected. The pump loads up normally but the machine turns real slowly. Not sure yet if it changes when cool. Not a drive chain issue, reluctant to swap motors as I am pretty sure it's a big job. Oil is maybe 10 hours old as are hyd filter and bronze screens. All help much appreciated.....