I took the boat out for the first time 2 days ago and it wouldn't idle for more than 15 secs without fast idle lever 1/4-1/2 up. i had a fresh tank of new gas/oil. Thinking it's probably just been sitting for a bit, i ran it at medium throttle up the lake for about 20 min total and it ran fine. At the end of the run, it still wouldn't idle w/o fast idle lever but ran fine under load. Took it out again today, same idle problem, but ran fine for about 20 min at medium throttle, then started surging, losing power, and left us stranded for about 20 more minutes. I finally got it back running again and every 5-10 min it'd start surging for another 5-10, then run fine but with limited power only. For most of the trip back, i could barely go faster than idle speed or it would induce surging. I'm calling the shop tomorrow to report this as i just purchased this boat and was told it ran fine. Could this possibly just need carb cleaning or new plugs? I fear the shop will run it fine with muffs or low speed in a tank for a few min and never encounter the problem.