JD 3010 Cannot lower 3 PT hitch

[wesler]

I was out mowing on my old john deere 3010 and backed my mower deck into a stump hard enough to raise up the front of the mower deck and the 3 pt hitch to the high position.
I pulled ahead and went to lower the 3 point hitch back down and nada, the 3 pt arms are stuck in the high position and will not lower.
The rocker shaft cable and lever on the side of the hydraulic case are moving normally, and I cant see anything that is binding or holding it up and preventing the 3 point from lowering.
Could it be something inside the hydraulic motor/piston that is broken? I never heard an unusual noise.
Any insight as to what is holding the 3 point up? Anything I can check?
thanks in advance

 

[wore out]

First of all, be VERY careful and stay clear of the implement, in case it should suddenly fall.

Does moving the "load and depth" lever have any effect?

<img src = "https://i.imgur.com/Zg8xcIo.jpg">

I suppose it's possible the "link" between the hydraulic piston (7) and the rockshaft arm (11) has somehow come out of place???

Link is supposed to be retain by spring pin (12).

If you have a loader or some sort of hoist available (if you can do this safely) you could unhook the mower and manually lift and drop the hitch arms to see if the link would drop back into place (IF that's the problem).

 

[Tx Jim]

Yes rod(key 7) in wore out's photo can move out of piston BUT will move back into piston as soon as rockshaft lowers. Rod moving out of piston allows 3 pt draft arms to freely float op/down.


My guess is cam follower(item 8) isn't in correct position in 3 pt control linkage or is broken. One can visually inspect part of linkage through bung hole in rear of trans case. Access to a bore scope would be a plus. If cam follower is the problem one can repair tractor by R&amp;R of valve housing.

 

[Tx Jim]

I also think spring(item 25) could be broken or become unattached.

 

[wesler]

I removed a panel covering the hydraulic case below the seat, and disconnected the rockshaft cable. I tried moving the
rockshaft lever by hand.It seems to move a little too freely,as though it is not moving much of anything inside the hydraulic
case.
No response from 3 pt at all,no lowering of arms.
So seems you are on the right track as far as that linkage somehow becoming disconnected.Possibly hyper extended when mower
backed into stump?

 

[wesler]

If the linkage inside the ROCKSHAFT CONTROL VALVE HOUSING has indeed become disconnected or worn, how is that repaired? does
the whole rockshaft control need to be removed and taken apart/rebuilt?
The lower/raise lever on the side of the case looks like it is mounted to a large hex nut.Can this be removed for access?