Good Day All! Got this at an auction, said it runs great. And it does, but it sometimes won't go to the high pressure. When it does it will really go to town! So I figured just put an unloader Assembly in it and problem solved. But after doing that, the same, with it running and low pressure and the trigger open if I choke the engine or throttle it down then it kicks to the high pressure and works great till I release the trigger. Then back to low pressure mode no matter how many times I cycle the trigger different nozzles I try. Thanks in advance for the help!! Steve
#2
kbowley
Try tightening the bolt on the unloader spring a turn and see if that helps.
I suspect that there is corrosion blocking the flow passages that feed pressure changes to the unloader valves. With the unloader out look inside the pump. There will be a hole drilled into the side of the threaded or press in area where the unloader sits. That passage is most like partially blocked.