Kubota M5700 Hydraulic Shuttle wont go forward or reverse

[Aeromechanick]

Greetings all, first post here.

I own a Kubota M5700 Hydraulic Shuttle that is used for mowing brush mostly.
Today I was extracting a stuck vehicle (massive snowfall) and the tractor was working great.
I pulled the tractor into the driveway, neutralized the shuttle shift lever, took it out of gear and applied the parking brake.

When I remounted the tractor 60 seconds later, I throttled up to 1500rpm, let off the parking brake, depressed clutch, put it in gear, flipped the shuttle shift to forward and let out the clutch.

nothing.

Moved the clutch, shuttle shifter into myriad positions…nothing. When I let out the clutch it doesn’t even vibrate differently…just smooth running engine, no tractor movement whatsoever. No perceived clutch engagement, slip, chatter…no sensation of any mechanical engagement at all.

It’s cold out.

I popped the hydraulic shuttle valve cover off, all linkage is intact and functioning. When I actuate the clutch, the valve spool shaft moves in and out. When I move the shuttle shift lever, its associated valve spool shaft moves in and out corresponding to the fwd, neutral, and reverse detents.

Did I just shear an o-ring off inside and fluid is bypassing?

Are those bench repairable?

Please help

Happy Friday to all!
-Nick

 

[North Idaho Wolfman]

Do you have the WSM?
Very uncommon for a shuttle valve to just go south!

Start with the simple things:

Have you checked the range lever?
I've got my money on this one!

Have you checked the fluid level?

 

[Aeromechanick]

Do you have the WSM?
Very uncommon for a shuttle valve to just go south!

Start with the simple things:
Have you checked the range lever?
Have you checked the fluid level?

I do have a WSM with Hydraulic Shuttle supplement. There is very little in the supplement that is helpful other than it acknowledges that a wet clutch is involved and hydraulic shuttle valve is present, how to split the tractor to replace the clutch or trans innards, and how to R&R the shuttle valve assembly and check it’s rigging.

no troubleshooting steps or suggestions.

trans/clutch/gearbox is serviced to high level index mark with brand new udt2.

will check and verify all other levers mañana to verify once more per your suggestion.

thanks for the dialog so far!

 

[Tx Jim]

How many hrs of use since hyd filters were changed? Have you checked hyd oil level recently?