John Deere 2020 Hydralics

We have a John Deere 2020 about a 1965 or so lately the hydraulics have struggled to lift the Hay bine. We changed the hydraulic oil but no improvement. Is there a screen in the system?
Has anyone ever had a similar problem? What was the fix?

Location of hyd screen is shown in photo.

When you clean the screen you should change the filter as well, if you haven't already. Its the cannister just ahead of the screen.

Do you have an Operator's manual? If not go to https://techpubs.deere.com/ . Click on the Equipment Publications tab. When that page opens enter 2020 in the box beside Model # and search. You should get a dropdown list of equipment with 2020 in the model #. Click on 2020 at the top of the list, that should open another list of just 2020 items. Look down the list to Tractors - Base Units. There are four choices, for North America (guessing you have a NA unit), to pick from, select the one that best matches yours by type and serial number (I expect your is one of the two utility ones not a grove model). When it opens the list of manuals you should see Operator's Manual and to the right of that it should say Download. Click on Download and you can download and save a free copy of the Operator's Manual. If you want a book or CD the prices for those are shown below that, they are not free. The parts catalog, service and/or technical manuals are available for purchase there as well, if you are interested in those. HTH[/url]