Duetz Allis 5220 w/FEL hydraulic problems

[CWBrad]

I bought a Duetz Allis 5220 with a front end loader and for a while the loader worked ok but there was a whinning noise when the hydraulics were in use. I had a hard time finding a hydraulic filter for the tractor so I could change the fluid so I used the loader as it was but not very much. While using the loader to lift drums of oil the loader quit lifting all together under a load. With no load the bucket would lift but very slowly. I parked the tractor unitl I found a filter and change the filter and the hydraulic fluid. That made the whine go away but the bucket will still not lift anything much. It stopped lifting very suddenly, it was not a gradual thing. I put a landscape rake on the three point hitch to see what it would do and with the lift up everytime I try to lift the bucket the three point hitch goes down. It seems to not have enough pressure and I wonder if the relief valve could be stuck? What do I need to chech and how to I go about checking everything out?
Thanks.

 

[J_J]

You will need a good manual.

If all things are good as in piston seals, and the pump is capable of producing flow and pressure and the relief valves are working, when you move a valve leaver, the cyl you are directing the fluid to should move when the pressure can overcome the load.

If the seals are bad, or the relief is sticking, and the pump is worn, then things will not work as advertised.

To check things, you really need a flow and pressure gage and determine if the pump is capable of flow and pressure.

If you have no or very little hyd, then you need to trouble shoot and find out what is good or bad, using pressure gage, flow meter, good manual, and some professional help.

You do know that the hyd components such as cyl or hyd motors develop the pressure, by doing work. If the pressure is to great, the relief valves relieve the pressure for safe operation.