I recently put a new shut-off soleniod. When first installed it worked fine. Now it is having trouble. When I go to shut down, the the soleniod releases. The engine stays running until I press down on the shut-off rod on the pump. I have tried disconnecting the shut-off soleniod wiring harness to verify that there is not a small current keeping it on. I have also adjusted the Hiem joint on the soleniod all the way out with no luck. It seams that the soleniod spring is not strong enough, but I'm not sure. It takes a fair amount or pressure from me to shut it off also. Any sujjestions?