I started a similar thread last year but I still have this problem. Even the guys at OSO seem to be stumped. I have Zeiger full dual ram, helm back power steering. It was fine for 2 seasons but at the end of last season I got play in the cylinders and had to bleed it. I was able to get all but about 1/8" of play out of it; It used to be rock solid. Now this spring, the same thing. I bled it repeatedly and was able to get it to about 1/8" of play. Boat ran great several times out. The steering still had about 1/8" play so I figured I'd re-bleed it and be good to go. Now after just sitting out of the water for a couple of weeks I am back to about 1/2" of play in the cylinders. The fluid level has not dropped and does not appear to be overheating or foaming. I have tightened all fittings and inspected all hoses and components. Any ideas?