Hydro problems Toro Groundsmaster 4000D: I have had the pumps on my mower rebuilt and have re-installed them on the machine with no problems. I was surprised the machine didnt need its neutral switch adjusted being re-built but seemed to be good in the shop. I mowed with it for an hour and when I parked the machine it creeps backward now. I have tried to adjust the neutral switch like the book suggested but doesnt seem to have any effect on the problem at all. I also unhooked the linkage from the hydro to see if that was the problem but didn't make any difference either. What else should I try?