Looking into buying a boat with Seastar hydraulic steering that was on the boat when new.It's a 1998 Hydra-sport LS205 with a 225 Johnson. Took it for a ride and I noticed when I was doing 65, the steering seemed hard to turn. When I shut it down to idle around, the steering was fine. 4 days later I asked the owner to check the fluid level and he said it was about 1/4 inch from the top. He did say when he took the cap off he heard air come out. Is this normal. It sounds like I need to bleed the system. Any feedback would help. Thanks