D5B with intermittent steering clutch

[Ferdinand]

I have a D5B, powershift transmission, 25X serial number, hand levers and foot brakes.
Recently one of the drive clutches has started intermittently sticking in the disconnected state.
Fluid levels, filters, linkage adjustments are all as specified in the manual.

When the clutch works right, it can spin the track against an overloaded blade,
so I know the clutch is not worn out. Just started to stick in the fully disconnected
state one day. Is this a known problem? My guess is that the hydraulic control
valve has a failure, or the piston that activates the clutch pack is getting stuck in
the fully applied position. Have never taken either apart, so I was hoping someone
has dealt with this before that can give me a pointer on where to start looking.

 

[Dave Neubert]

pull the access cover off the back of the machine you can then look in there and see if the hydraulics are releasing or not

 

[Ferdinand]

Thanks for the reply. Just found that the hydraulic actuator valve has a test port in each side that drives the steering clutch hydraulic piston. Easy to get to and that will show me the pressure in the piston at any given time. Looking at how the valve works, I'd guess that the return spring may be boken or something is roaming around in the spool, making it stick in the on position.