I have been trying to figure out my issues for a few weeks now. My original issue had to do with a plastic washer on the wheel that broke off. This allowed the chain to continue coming off of the wheels. Replaced the washer and it seems to be fine now. It also appeard that the backup valve had gone bad so I ordered a new one. This one also seemed to be acting up so I replaced it with another one. After fixing all of that I looked out and it appeard that the machine was running very slowly. After observing it I noticed that none of the wheels were rotating at all and the machine seems to be almost laying on its side moving in a circle due to the water pressure from the backup valve/hose. Any idea what might cause this. It appears that my pressure from the inlet is fine. I haven't checked the new backup valve yet, but is there anything that would cause these to keep going bad?? I don't mind tearing the unit apart (I have been in there a million times) but just not sure what to be looking for?? Thanks!