Tractor is a B1550 Kubota- why is hydraulic fluid getting in the crank case?

SOURCE: John Deere 1020 Weak 3 point hydraulics

I would suggest you find a JD dealer and buy a manual if you want to do the maintenance yourself. You can also do a Google search and find manuals.

I would also suggest you completely drain the old hydraulic fluid and replace it with new fluid and a new filter if it has not been serviced any time in the recent past.

The symptoms you describe can be low fluid and/or a clogged filter. If you or anyone else has run the tractor too long and it has low fluids and/or a clogged filter, you can damage the hydraulic pump and that can get costly.

SOURCE: I just purchased a 2440 john deere tractor it was

would say that your variable displacement pump has rust or other on/inside, it.

Are you using hydralic fluid (not eng oil) in her?
Can you let it run on blocks for a bit - drain and re-fill transmission?

SOURCE: i have a case 4210 farm tractor and need to know

Older case machines used a fluid identified as TCH (Torque Converter Hydraulic) for both the transmission and the hydraulic system. It's not readily available so has been replaced by default by separate products. Hydraulic fluid for the cylinder system, and transmission fluid for the torque converter. I'm currently using NAPA TDH with no problems.

SOURCE: Ford TRactor 1710 hydraulic problem

raise front loader....loosen hyd. line a little lower loader till all air is released and only fluid is coming out and retighten.....its like bleedig brakes on a car

SOURCE: 2090 case trasmission problems

That's because you have two separate pumps controlling each. My best advice is to get a farm mechanic to take a look...it may be a simple seal to a need for a rebuilt pump. www.nyagparts.com