I have a 65HP Johnson 3 cylinder, I think it's a 1972. Anyway I got it out and got it running. I had pulled the carbs apart over the winter to clean them. Had to adjust the linkage. Shut it off and restarted it. It seemed to run fine. I was using earmuffs connected to the water hose for cooling. I started noticing steam coming out of it so I pulled the gas line off to use up the gas in the carbs and after about a minute it shut off like I had turned the key off. I found that I had not positioned the earmuffs properly and was not getting enough water in the motor. Repositioned them and tried to start the motor again. Did some checking and found that I had no spark to all three cylinders. I didn't run it very long so I don't think it overheated that much. My question is; Is there a over temp switch that would shut off the spark or would overheating make the power pack give it up? Any help with this will be greatly appreciated. Thanks