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Case 580C Steering

Notorious B.O.B. · 2023-03-12 15:10

I bought a 79 580C. There steering seemed to work when I picked it up but very soon the steering wheel just started spinning. I realized it was losing fluid from a bad steering cylinder (RH) which I quickly replaced. Now the steering works fine when I lift the front end with the bucket but when I set it down the wheels only turn to the right and lock up turning to the left. I have checked to make sure the hydraulic connections are correct. Could this be the pressure relief valve in the pump? Thanks in advance for any feedback.

Replies9
  1. #1franklin22023-03-12 15:36

    We have had a couple of threads recently on this. The first one ended up the hoses where hooked up wrong. The poster assumed they were hooked up correctly by the mechanic, but he had indeed hooked them up wrong. I think the second one ended up being the piston inside one of the cylinders had come undone. So the piston was moving internally without moving the cylinder rod.

  2. #2franklin22023-03-12 15:42

    Here's one of the older threads. HeavyEquipmentForums

  3. #3Notorious B.O.B.2023-03-12 17:14

    Thank you Franklin2. I read those threads. The hoses are correct and the cylinder rods move fine when the front is lifted. When there is weight on the front wheels though the steering locks up when turning to the left. If anyone has run into this let me know. I'm going to go ahead and replace the power steering pump and see if that does anything but I'm not sure why it would.

  4. #4Tinkerer2023-03-12 17:49

    Before you replace the ps pump did you check, clean or replace the filter in it ?

  5. #5Notorious B.O.B.2023-03-12 17:51

    No but I'll do that now.

  6. #6Notorious B.O.B.2023-03-12 20:05

    The filter seems ok and the fluids were good. I'll drain the whole system change the filter anyway before I replace the pump and see what that does. Could it be the pressure relief valve? I may see if one is available I welcome any other thoughts in the meantime.

  7. #7Acecadet2023-03-12 20:59

    Check the relief valve before reassembling the pump. I’m thinking a left turn is using the smaller diameter of the cylinder thus it would require more pressure. That’s why it won’t turn left with weight on it. I circled where the relief resides in the pump.

  8. #8Notorious B.O.B.2023-03-12 21:03

    Thanks! I'll check it out.

  9. #9Notorious B.O.B.2023-03-21 16:23

    FYI - I replace the pump and all is well. The filter wasn't the problem so I am guessing it was the pressure relief valve.