Motor is on 20' pontoon boat and had motor rebuilt less then 1 month ago. I've had it out once and runs fine at 1/2 throttle and less, but running WOT for any amount of time and motor dies. Needless to say it's been sitting with the mechanic for the last week, but he seems to be at a loss as to why. He says he can get it to start and run, but the next time it will be hard to start so he thinks it is electrical, but so far everything tested fine for him. <br />Brief overview - lost lower cylinder - new sleeve, piston, rings, etc. installed. Now this. Anyone have any ideas?<br /><br />Thanks in advance.<br /><br />Bill