I have a older case 580b ck forklift and the steering gradually was going out, so I changed the hand valve the the steering wheel mounts on and the PS pump-also took apart the steering control valve (which looked ok) But steering will not operate with the the wheels on the groung-but if i jack up up the axle and take off the weights=it will work fine. Does anyone have any ideas on what to do nex ?
Pump doesnt have the efficiency to turn the wheels under load anymore?
I put on a new steering pump
is it possible that 1 of the steering cyliners or both have bad inner seal allowing fluid to bleed by ?
I put on a new steering pump already
Yes it is, if that were the case you could just about hear it. If you take the line off the side opposite of what you are pressurizing, the fluid coming out of that port sould be minimal
There were some of those replacement steering pumps that had a problem, if you didn't put oil in them and turn by hand to break in they would burn up immediately when you installed them. Case, to my knowledge never addressed the issue because they were changing the steering system on the "D" series. But yes you need to check you steering cylinders anyway.