Slowly Sinking Woods?

[rpeter]

Have a B7800 with a woods BB60 BrushBull on the back. Use the combo to cut weeds between the 12 acres of trees we planted last year. I have been having increasing problems this year with the cutter slowly sinking to the ground as we do the cutting. We have to check the height and readjust it about every 10 minutes or so. It is absolutely impossible to maintain anything that resembles a level cut.

I have about 65 hours on the tractor. We do not use the FEL as much, but do not seem to have any problems keeping it up. Any suggestions on what the problem might be?

 

[GuyL]

Have you tried setting the "stop" (wingnut set screw located below the 3pt control lever) to stop the implement from going below a certain height? Another suggestion is to buy a set of chains to keep the height constant. I have used the chains on an old tractor with weak 3pt and they work great. Cost about $50.00 but are easy to use and you always have a consistant cut.

 

[Av8r3400]

RPeter - I'd say you are in need of a 3pt control valve rebuild. With only 75 hours on the meter, it should be covered under warranty. Your 3pt should hold a brush cutter without a problem for several hour at least.


(Guy - your are discribing the control for a position control 3 pt, a B7800 does not have this, it has a 1/4"-ing valve.)

 

[JackIL]

I have a set of check chains that has never been used. Please PM me and I will make you a deal.

JackIL

 

[Bob_Young]

The B7800 does have 'quarter-inching' control of the 3 pt. hitch. From what I've read and experienced (B7610) they won't hold a position and will always 'leak' down UNLESS
1)the 3-point lowering speed knob/valve is closed with the mower set at the proper height OR
2)the implement lowering limit is set to your desired cutting height.
Be advised that with the lowering speed knob/valve closed, you won't be able to raise the mower without first opening the knob/valve. This would be bad if you hit an obstruction.

A second and safer option is to adjust the implement lowering limit to the desired mowing height by changing the position of the locking collar on the 3 pt. interlock rod (underneath right side of seat on B7610). With this limit set correctly, the control lever will be forced back to neutral when the mower is lowered to the correct height. In my limited experience, this works and works quite well without any leak-down; but it is hard to reach with the wrench and a minor PITA to adjust. Check your manual for details. The locking collar on mine takes a 12mm wrench.

IMHO Quarter-inching is a bug being sold as a feature. That said, if the above referenced lowering limit were made easy to set (say with another operating lever instead of a locking collar), quarter inching would work quite well as a low cost subtitute for position control. The fact that it isn't easy to set speaks volumes about the Kubota marketing mindset.
Bob

 

[DAP]

I believe your machine should the be level in the back as long as the machine is on and the pump is pumping.

They will leak with the pumps shut down (engine off) though .. but it should not be drifting down while the machine is running.