574 Hydraulic troubles

Hi. My 574 has developed some hydraulic troubles. No power steering, three point is stuck in the raised position, and no flow/pressure to the scv's. Also the pump sounds like it is under load all the time even when there is no demand. I just changed the fuid and filter to see if that would help, but it didn't make any difference. Anyone have any ideas?

Hi Mad, was there and hydraulic oil in the filter
housing when you changed the filter? Does the 574
have remote hydraulic outlets? Make sure the
remote control valve has returned to the center
off position. So 3pt will not go down even with
engine off? The hydraulic system is an open center
system, which means in the idle condition (no
control valves being activated) the hydraulic oil
is always circulating. For 3pt and draft control
and remotes, the high pressure line is lower right
line on MCV behind the filter, the return is the
line above the high pressure line.


From Bernard le Mecano,3 pt will not go down:

There is a cover on the right side under the seat
in front of the rock-shaft. Remove and check if
the spool valve moves with the position lever.
Make sure the draft control lever is down. It has
a long spring, with a rod, maybe the spring is
unhooked.

Hi, maybe the unload valve is stuck. Check with
engine running, raise the hitch and at the same
time pull the remote hydraulic lever. If the hitch
raises, there is dirt in the unload valve. This
valve is under the seat and you have to remove the
large plug for access. One trick, loosen the large
plug, unload valve about 2 turns and start the
engine, the 3pt hitch should raise if the valve is
stuck. It has a small hole in the valve and just
blow the dirt out with air. Replace with new O
rings.

Hope this helps
JimB