I have a case 580B that has sat for a while. When i got it started it would not go forward or backward . The trans pressure gauge on the dash reads in the center of normal. When i push the clutch pedal the gauge drops to the bottom as it should. when i let the pedal out the backhoe does not move. I hear a strange noise and the lines that go to the trans filter in the front of the machine vibrate and make noise. i did change the trans filter. Any one have any ideas?
pull the pan down and check the suction strainer.
Don't think any B's have a pan to pull, pick up tube is inside torque tube, have to split the tractor or drill and tap a hole to access pickup, maybe can get at it if you pull control valve off top. Check out GRT Ranch Adventures on the you tube. Dude has a couple in depth videos covering shuttle valve rebuild and general shuttle operation videos on his 580B. maybe worth a look. If machine sat for a while you may have rust preventing components/check valve stuff from allowing flow through the control valve on top of trans. Watch the videos.
I don't think it is the pickup tube ,because sometimes if you pull the clutch pedal up by hand real hard the shuttle works fine. I will watch the videos on you tube. Thanks guys.