Just recently my machine (5.5 gpm 3500 psi)..was running fine using cold water and suddenly it started to randomly lose water pressure..on and off the pressure went as if I had no water supply. ( It's tank fed) and it appears its not sucking the water from the tank. I hooked up a hose from the house direct and the machine/pump ran fine. I re-attached the tank supply and it would not take the water from the tank. The valve from the tank is clean etc. Any thoughts?.Thanks, Bob