Is it hard to steer out of the water?
If so, disconnect the steering cable at the back of the boat and then check the steering. You should be able to do disconnect it with one wrench. Then try to steer it. If it's easy to steer, the problem lies in the nozzles. Specifically where they pivot. There is a plastic bushing with a stainless insert. You can carefully press out the bushing. The proper way to do it would be to ream the holes with a reamer---but I'm sure no one would have that in their tool box. So, get a wooden dowel and wrap some sand paper around it and clean the hole up real good. The bushing should very lightly press back in with your fingers. Also, the bushing should pivot on the stainless sleeve that the nozzle bolt goes through, so you may need to clean the bushing up with a drill bit. Perhaps to make it real easy, just clearance the bushing for the sleeve and don't worry about sanding the nozzle. If it does, put it back together and your good to go. I had the same thing on my Speedster, I had to man handle the steering wheel, now I can steer easily one handed while cruising along. Pay close attention to how everything comes apart---even the bushings. The nozzles corrode squeezing the plastic bushing, which in turn squeezes the stainless sleeve, thus making you look like The Incredible Hulk while steering.
http://www.shspowersports.com/fiche...&make=Sea-Doo Sport Boats&year=1997&fveh=2708
#54, 31, and 5 are what your looking at.