1953 Ford Jubilee 3pt hydraulic lift problem - only lifting from 50% and above

[tacker]

Went out to brush hog today and mowed for about 2hours then all of a sudden my brush hog went straight into the dirt - I lost the first 49% of my lift - I could raise it 50% or above and keep the hog 2-3ft in the air but when i tried to adjsut it to about 6 inches off the ground the lever would just fall down and put the hog in the dirt.
What would cause the control lever to just drop like that from the first 49% down but then grab and stay from 50% there on up ?
One other thing I did notice is that the Hydraulic fluid was over full - would that cause any problems ?
After the tractor sat for a couple hours everything seemed to work correctly ( although I didnt have anything attached at the time )

 

[jinman]

Look at the shaft where your lift lever attaches. That shaft has a friction plate and friction disc. The pressure on them is adjusted by the nut on the end of the shaft. It should have a spring behind the nut. I'd guess that your friction disc is probably worn in the lower part of the quadrant and friction is not evenly applied throughout its movement. You can purchase a friction disc or make one yourself out of leather. I'd try to tighten the nut first to see if it will hold satisfactorily before putting in a new friction disc.

 

[tacker]

Thanks! That's Exactly what it was!