Big Mo 500 power steering

I rebuilt pump but power steering still not much force. With a load in bucket it will not turn easy. Remove load in bucket and it still will not turn easy. Next time you start up it turns easy. Also it turns easier one way than the other. Anybody know what may be wrong

That question is too big at this point, there are too many possibilities. First I would make certain that the mechanics of the steering will allow for easy turning, steering U-joints, thrust bearings, spindles, knees, etc. When those potentials are eliminated then look into the pump and hydraulic oil supply. If a 500 is like it's relatives, you can disconnect the lines that go to the steering cylinder, install a couple of stub lines and check the flow when operating the steering. You may find a good strong flow in one direction and not the other. You may have to disassemble that control valve and check some clearances according to a service manual. You may find that the hydraulic fluid flow from the pump to the control valve is inadequate in terms of volume and that could be caused by the slightest obstruction in the orifice that controls the amount of hydraulic oil allowed to be used by the steering system. You've got to start digging, eliminating possibilities to zero in on the problem. Few things are as annoying than a machine with power steering that is difficult to steer - not that I've ever experienced this problem, LOL
CC

I've had spindles out and replaced thrust bearing (they were bad). I'll go from there thanks for the suggestions.DIM

Curt, I think your advise is right on and I couldn't agree more with you on it.