3-Point Hitch Hydraulic problem

[rosso01]

I have a 1987 John Deer 850 tractor that was working fine before I changed the Hydraulic fluid. Now, the three point hitch raises up every time I start it and you have to hold the lever down to lower the hitch. Is it air trapped somewhere? How do you bleed these tractors?

Thanks

 

[Tx Jim]

Air will bleed by cycling 3 pt hitch up/down. Is the friction mechanism(parts keys 19-26) snug on the control handle.

 

[rosso01]

Thanks Jim,
I guess this is not a bleeding problem, we have been working it up and down all day. I looked and found the friction mechanism is completely missing, i can fix that. There is a knob under the seat that has open and close on it. It looks like an outdoor garden hose type. Does anyone know what this is?

Tanks for your help.

 

[Tx Jim]

There is a knob under the seat that has open and close on it. It looks like an outdoor garden hose type. Does anyone know what this is?.

Knob is 3 pt rate of drop screw. CW slows 3 pt CCW speeds the lowering time. Screw can also be used to lock 3 pt in raised position. Put the friction bolt,nut & spring on & you'll be in business.