I have a Hayward Viper (Model 5500 bought in early 2004). Last year I had a problem where it would keep spinning in circles (stuck in "turnout" mode). I found the check valve was cracked so I replaced it; problem solved.

This year, after running normally for awhile, it will get stuck in "turnout" mode, just spinning in circles like it did last year. I took a look at the check valve, but I can't see anything wrong with it. I opened up the manifold and cleaned it out thinking perhaps that it was getting stuck in the "turnout" position, but that didn't seem to help. I checked the cam gearbox, no problem there (the cam is turning normally).

I thought I might just go ahead and replace the manifold (part #AX5500MA) and check valve ( part #AX5000CVA), but I've discovered that Hayward changed the manifold design in mid 2004, and according to at least one website, the new manifold (part #AX5500MA3V) won't work in my earlier Viper model.

Any ideas what might be causing the problem? Any help/guidance is greatly appreciated. I'm really hoping to avoid having to get a new one ($$$) if i can fix my Viper.