I need to replace the unloader valve assembly on my Generac G24 pressure washer pump. The pump is a model 1537-1 and I have the replacement kit. My problem is that I cannot unscrew the existing unloader valve nut. The nut is flexible, (hard rubber, plastic - NOT metal) and as a result, wrenches, sockets, vice-grip pliers all just slip around the nut. I certainly cannot replace the old valve if I can't unscrew the damned nut!!

Has anyone had this problem, and if you did, how did you remove the unloader valve nut???

Help !!!!