Dwight; We're almost there. On my version of the diagram you posted, if you were to put valve 005 between the pump and the pump discharge valve 004, you'd be able to control discharge pressure and flow by throttling valves 004 and 005. If you had too much flow and or pressure, open valve 005 and recirc back to the tank. I said a globe valve would be the best type for 005, but a ball/cock valve would be fine too for the purposes intended. Now if you really wanted to get crafty, you drill an orifice in valve 005 vavle seat, and always have a flow back to the tank. I don't think you need to get that elaborate tho, we're not talking 4200#psi and 3,000,000 pounds per hour flow. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif