Tractor Repair: Ford 3600 early, hydraulic control valve, bush hog

Question
Mike,generally, could you explain draft control selector and lift control selector and what one is supposed to do with the other? my ford has an adjustable stop  on the draft selector quadrant and I am not sure of setting for it.Lifts and holds my bush hog just fine but not sure of relationship of draft lever to lift lever.

Answer
Ron,

On a tractor that has draft control, the draft control lever sets the sensitivity of the draft system. "Draft" refers to the hydraulic system's ability to sense and react to the pulling load of the 3-pt hitch.

On your tractor, the tractor,s top link(center link) clevis can move in and out slightly. It is actually connected to the hydraulic control valve inside the tractor.

If you were pulling a plow, and the plow hit an underground rock or root, the plow would be tilted forward, which pushes the top link "in". If the draft lever is set to the most "sensitive" position, the hydraulic system would automatically raise the lift momentarily and then return the plow to its original position (based of the position of the "position" lever). All of this happens without you stopping or making any adjustments.

If you have it set too sensitive, the plow will raise up all of the time under even the slightest loads. You may have noticed that if you move the draft lever to the top, the lift might raise all the way up suddenly.  If you have it set too low, the plow won't raise and you could get caught on the root or tear something up.

On Fords and Masseys (and most other tractors) draft sensitivity is highest at the up position and lowest and the bottom position of the draft lever.

For most bush-hoging, mowing, blading, discing, planting, etc., the draft control isn't even used. I'd set the draft lever about 1" up from the bottom, set it there with the stop, and never touch it again.

As tractors get older, the internal linkage gets worn out and the draft lever's position varies. So, the actual placement of the draft lever isn't that critical in your case. Just keep it on the lower half.

Hope this makes sense!

Mike