I'm new to this forum and new to PWC ownership. I bought a pair of 98 ski's and one of the machines wouldn't run. I replaced the fuel filters and spark plugs and a new battery. Took it out yesterday and it ran like new (only has 70 hrs on it) for 3.5 hrs. I went back out today and it ran great for the first 30 minutes then wouldn't go over 3500 rpm and 10mph. Don't know where to go next with this one. Any help???