JD 2040 (year 1980) rock arm (bushhog) stuck in up position

[SennaMiller]

Hit a stump or log bushhogging. The draft control will normally raise the bushhog when it hits something (feels resistance), I also raised the lever to elevate it slightly. Apparently the draft control raised it up into the full up position, but it will not go back down. Tried leaving it sit overnight, it did bleed down slightly, but as soon as I turned the tracctor on, it went back to the full "up" position. I have been able to make all the repairs to this tractor so far over the last 3+ years of ownership. I sure would appreciate any thoughts about what could be causing this. My initial thought is that the draft control (resistance control) has failed, but not even sure where it is located (assume in back top internal of tractor). Please let me know any suggestions for how to approach this. Also, is there a bleed valve anywhere which I can use to lower the bushhog so I can remove it (if it needs to be removed for this repair)? Your help is very much appreciated. Senna

 

[Doc]

Hi and welcome to Net Tractor Talk.
Interesting problem. I've never seen anything quite like this before. Interested in seeing the solution.

 

[bordercollie]

Did your foot happen to hit a lever or knob about where your heel would be resting on your open air JD? On my open air Kioti, there's a draft knob there . And I hit it once by accident , took a bit to figure that out.
edit: forget what I was thinking and look at this link. The pictures are bad but it does give information on the lift. https://www.tractorjoe.com/manuals/...nual-2040-tractor-266715?page=21#manual_42_21

 

[jdgreen]

There is a rate of drop control under the front of the seat. Some models had a lever and some had a bolt head that needed a wrench. Make sure it didn't get turned full clockwise. That would prevent it going down. Have you tried moving the draft control lever as well as the height control? Draft control should be in minimum position for a rotary mower. That should not prevent lowering however.