I just had the solenoid replaced on my 518H. When it came back from the shop, I tried to mow with it; however, when I engaged the PTO, the engine would shut down, very like it would do if you happened to fall of the mower while mowing. I looked at the switch and when I engage the PTO and manually press down the levers on the switch, the mower will continue to run. I am trying to figure out what is going on. Could something have been switched at the solenoid replacement such that the safety switch on the PTO is backward? Any help will be appreciated.