I have a 1999 30 horse Johnson jet (40 powerhead)2-stroke tiller motor. It ran great last year (but I was not the last person to use it last season). The first time I took the boat out this season it ran great for about 10 minutes, and then started kicking repeatedly about once every second or two. I figured it was water in the fuel, then air getting into the line. Basically, I have replaced the whole fuel line including the fuel pump, and added a raycor fuel filter. I have drained the carbs, and changed the plugs. <br /><br />In my search, i also discovered tiny bits of gravel in the thermostat and have cleaned that out several times until the gravel stopped showing up. I also removed gravel from the exhaust manifold (where water looks like it would flow into the pistons).<br /><br />I just ran it this evening and right around the 10 minute mark, the motor started kicking again about every second or two. Once that happens, I cannot rev it up because of all the popping the motor does. I have to travel at an idle speed, or barely above idle. I basically have met the limits of my general maintenance skills. Could this be an electrical problem? Is the motor overheating and it is shutting down? I would appreciate any advice people may have. <br /><br />Thanks,<br /><br />Michael
