Legbreaker - Sorry to be the devil's advocate - and this is just cheap information. (You've been had) This steering system has 4 primary areas: power steering cylinder, steering orbital motor, diversion valve (priority valve for power steering, right hand side of the tractor where all the hydraulic hoses go to) and the main hydraulic pump. If both left and right steering failed, the steering cylinder cups are probably ok. When the steering fails, do you still have your 3 point lifting power? That would tell us if your pump is losing pressure. OK, now then, considering the above is ok, we're down to the proportioning valve. This valve allows the power steering to operate at a lower pressure than the 3 point lifting power does. (Otherwords - should have power steering over lifting power) The worst scenario is the power steering motor. They are very complicated, but can easily be worked on by an experienced mechanic. They have a cylindrical cylinder that hooks to the steering wheel with 101 holes(maybe) less than an eight of an inch diameter, and a stationary housing tube with 101 holes. This has to be timed and installed in the proper sequence. They also have an orbital hydraulic gearing in them. OK, My only suggestion would be to unhook all the lines from the portioning valve and steering motor, and blow compressed air back through all ports. I guess what I'm trying to say is that once in a while part of the hydraulic hose flakes off and gets into the system. Be sure to have a dealer that fully understands the operation of this system, rather than just replacing parts. Hope I'm all wrong, and you find a simpler answer. Keep us informed. Yugo