here's the issue
took it out, ran great for 1.5 hours, then it started to lose power acceleration and after about 20-30 minutes i was down to 30/25 mph
took it home changed spark plugs, added gas, took it back out
ran good for about 30 minutes then it began to do it again, but quicker, after 30 minutes i was down to 10 mph, i have a 2001 seadoo gti, ran great last year with no issues, unwinterized it, and now have this problem, any help would be appreciated, thanks