OK, 580B I was emptying a manure pit (we call it **** pit), had bucket in close to right wall, tire hit wall went ...90 degrees to the right. Tried to steer back out, no steering. Got it out of there, tested with bucket down wheels off the ground, wheels moved manually both left and right, no problem. With steering wheel turning left or right... well after mutiple (many) turns of the wheel right the tire moved and went to the stop and the wheel stopped. It won't do that to the left, and it won't do that when the tires are on the ground. I thought right away... steering pressure pump problems, look up the replacement pump, $675.00 so it can't be the pump. Thought well control valve jammed, took out valve, ... looks ok to me, how do I test it. Then I thought, well maybe the manual steering pump (steering wheel, that controls the control valve) might be bad... Or could have blown out the wheel hydraulic cylinders? How do I test the: Pump Control vavle/spool Manual steering wheel pump Wheel cylinders I did take off a hydraulic hose off the left side and into a bucket it flowed fluid when I turned the wheel either left or right, so I had assumed control valve problem. I need trouble shooting instructions. Thanks. Rancher
rancher, it is very possible that you could have blown the cylinder packing or if you hit the wall hard enough with the wheel turned you spiked the prssure and blew a seal inside of the pump if the relief did not relieve fast enough. You need to take pressure checks of pump pressure, and system pressure to make sure if the system has a relief valve it is not stuck or damaged. If I remember correctly the pump is mounted piggyback on the main hydraulic pump at the front of the engine. i do not have anymore case books but a dealer should be able to tell you where the pressure tap locations are. Hope that helps some.
Take the cylinders apart and see if the packing is blown or the nut pulled off the threads on the piston end due to hitting the wall, there is no relief valve on that end of the system. To isolate which cylinder is bad you can plug the lines to one cylinder at a time and see if it steers with one cylinder. Another way is to see which cylinder warms up as you have someone continually turn the wheel. The oil will get warm as it moves in the circuit and will flow freely through the damaged one warming the cylinder, it will be really noticable at the fittings. Mel.
Rancher, it sounds like a steering cylinder. You could do a leak path test. Extent the cylinder rod all the way out. Remove the hose on the end the rod is on and cap the hose. Turn the steering wheel the same way to extend the rod. If the piston seal is bad oil will shoot out the open port the hose was taken off. Try one cylinder then the other, connecting the hose back before testing the other cylinder. This might be a quicker way to test the cylinders before doing a lot of system testing.
How do you check the pressure, ... I mean you can't just close it off all the way, or can you? And no it is mounted like a normal PS pump on a car engine, except it is gear driven. I'll check the wheel cylinders tonight if I get the shuttle valve back together. Rancher
Thanks That was it, nut broke off the shaft in the right steering cylinder. Thanks All !!! Rancher