D-215 Heavy oil leak

Hello together, I have here in the shed still an old IHC McCormick D-215 (I guess from about 1963) stand. I hope with questions about this I am reasonably correct here. Or else someone might know an active, more meaningful forum for tractor problems? So, I finally wanted to make up for the old tug. As a child he was – always after school – my afternoon job on the yard of my grandparents – I can still operate it because it still runs quite ok, but he It’s not the engine oil, which drips out and it soups up in the stand, even if it’s not used for a long time, continuously whenever I don’t look at what’s out. There’s a big tub under it that catches everything. I suspect it’s hydraulic oil. But I’m not sure. I crawled under it a while ago, you can’t see a special place where it runs out because of all the big mess. My plan is to clean everything up in the next few days. d to observe again. However, I wanted to do a little research in advance, whether someone has experiences with something like this and maybe a few links or tips, which are probably the usual causes. Does anyone have tips? I would be very grateful because I don’t know exactly how to handle it at the moment. Thank you already! PS: That’s exactly the one it is (just found): http://www.fahrzeugseiten.de/Traktoren/IHC_McCormick/D-215/d-215.html