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CASE 780 Big problems LITTLE money

Roadscare ยท 2013-09-03 01:06

I have a CASE 780CK that has a unique problem that I can not find anyone that can give a definite answer as to how to fix. When placed in forward gear it goes in reverse, when placed in reverse it goes forward. It shifts from back and forth instantly, but has only about half the the power I think it should. Problem #2: As it warms up, power steering will only work under heavy RPMS. I have all the manuals but can nor figure it out.

Replies7
  1. #1csthompson122013-09-03 09:14

    The power steering problems sounds like the steering cylinders have bad seals. When the machine is cold the oil viscosity is thick enough to make the steering work. When the oil get hot, its so thin that it bypasses worn seals in the steering cylinders. Seals kits are inexpensive.

  2. #2Delmer2013-09-03 09:59

    Is this a new machine for you, or one that you've had for a while and recently developed this problem? Any signs of anybody messing with it? Have you checked the fluid level and condition? Or tried anything else already?

  3. #3Roadscare2013-09-03 14:55

    So you do not think it is in the steering pump? Steering cylinders are better for me, much easier to get to. THX

  4. #4Roadscare2013-09-03 14:57

    I have had the machine about a year, but only just got the chance to use it. I am a pretty fair mechanic, but smart enough to know that I dont know everything. Hoping someone would chime in with a golden nugget of knowledge.

  5. #5Tinkerer2013-09-04 06:42

    The first thing to do is a pressure check at the pump. #15. Do it when the machine is first started and then again when it is up to operating temperature. If the outlet pressure is good then I would next check the pressure at the cylinders themselves. That would verify if there is or isn't a problem in the steering valve or piping. If it is a steering cylinder problem reseal both of them. The piston may have to be replaced because, I think that the piston ring/seal is only available on a new piston. The price of those pistons will definitely bring tears to your eyes when you hear the price of them.

  6. #6Roadscare2013-09-05 16:27

    Thanks Tinkerer. Is that #15 a special fitting for the pressure check?

  7. #7Tinkerer2013-09-05 20:18

    I don't know if it is Roadscare. I would guess Case has a set of fittings along with the proper pressure gauge to do pressure checks. Take it off and use a clean grease gun hose with the needed fittings to hook up a gauge.