3 Pt Hitch

[rojoknight]

I have a MF 220-4 that is locked in the upper position. When I started the tractor it went up and frozed in that position. The tractors has been sitting for about five years. It's a diesel and I bleed the lines and it fired right up. The loader works, and the pto. The only problem now the 3pt does'nt work. Three tractors and the hitch does'nt work on all three. A curse? The nob under the seat is froze in the clockwise position which actually is the lock out position. I assume I remove six bolts, unfreeze the floating piston? Do I need to bleed off the hydrulic fluid pressure before taking the cover off. Never seen a engine I could'nt start or work on but hydrulics.....nada. Unless it's the hydrulics associated with a 5 inch. 38 gun mount. Telling my age huh folks? Newbie looking for advice. Thanks....

 

[J_J]

You should be able to remove the knob /descent assembly and unfreeze ot un-rust it..

With it locked tight, no fluid is allowed to flow out the cyl.

When you pull the lever to raise the 3pt, does it make any noise. .

If you put a gage in the input to the first valve , does it reflect any pressure.

For every lever you shift to max, the relief for that valve should activate.

If the loader works, that means that fluid is flowing through the 3pt valve, because you raised it up the first time.

With no valve levers engaged, the pump fluid is flowing through all valves in the series flow from pump to the tank.

Now the cyl is full and locked so, no down mode.

Make sure nothing is attached to the lift arms when you clean out the descent assembly.