/ CASE 485-HYDRAULIC PUMP? #1  


New member
Oct 17, 2020
Case 485 & MF 230
I have a 1990’s model 485. I am having hydraulic problems. I had a guy change the filter and priority valve. No change-sometimes it works right for a minute. Next time it not lift much and very slow. Other times it will not work at all. During these times I still have steering. I have been talking to my local Case dealer for repair options. The pump is in tranny housing correct? To fix it, the tractor needs to be broke apart right? The service tech at my local Case dealer could not tell from the drawing of it.
Thanks for any pointers/help/advice
   / CASE 485-HYDRAULIC PUMP? #2  
The pump is accessed from the left side of the transmission housing. Splitting the tractor is not required.
  • Thread Starter
That is good news. Any idea where the access plate is at to get to it? Are there any good online manuals?
   / CASE 485-HYDRAULIC PUMP? #4  
Your priority valve is sticky.
Remove and polish. 5a

View attachment 718040
Last edited:
   / CASE 485-HYDRAULIC PUMP? #6  
Let my tri and help
As you sit on the tractor ...move your PTO lever thats on your righthandside and check what moves under the floor on your left side. You will see a bowl(hydraulic filter) and under that you will see two plugs thats screwed in from the bottom. One is your priority valve and the other one is the pressure relieve valve. Remove the one with the spring and pull the valvespool out . Polish that spool till it slides freely .
Assemble and test.
  • Thread Starter
I got it out and I polished the priority valve. Is there anything else in particular that I can do before putting it back in? As I understand it, the hyd. pump does the FEL, 3 point and power steering. The power steering works fine. The FEL and 3 point is random if working at all. Since the power steering works I am thinking the pump works?