Since you brought this back...

My Walbro has gone the same way as the DW with regards to needing a longer prime. I don't think either has a long-term reliable check valve. Definitely, with my power level, I would have been much better off purchasing an OEM pump that has adequate flow and a long-term reliable check valve.

I have no confidence in aftermarket in-line check valves either.

I don't prime, then go to off and then start, however. Rather, I have a 2.1 second delay, which actually runs the pump for 5 seconds. Then I move switch from ON to START right after the pump stops.

DNM