I bought a 94 gtx. I took it to a seadoo mechanic to evaluate it. He said that it had an engine noise. He never had it in the water. On the trailer, I can't say that I hear anything unusual. I have tried putting a screwdrive to my ear and the engine and still don't pick up on any unusual noise. On the water, I hear a definite knock. The knock is there at idle, and not there if I give it a little throttle. It seems like it is there at full throttle, because of how loud the engine is when it is. I am considering ordering the anti-rattle kit, but I can't believe it will help. Engine runs great other than that. Gas gauge does not work and speedo does not work. Everything else is fine. I have $800 in it now with the trailer. Is it worth replacing the engine if it is noisy, or should I just part it out?