Backhoe L3940 HST 550hr. Random lockup of joystick positions, outriggers, reverse, FEL, etc

[JerryBuilt]

Hello, my first post! Thanks to all who have posted and helped me solve my previous problems!
L3940, HST BH, FEL, 3rd valve for grapple (installed by dealer)
During operation, I am experiencing random inoperative hydraulic functions. IE, the BH wont swing back to center, one outrigger wont retract, once I could not press the reverse pedal, and once I had very little engine power to make it back to the barn. It is like the levers are frozen in place. Then everything works fine. It started as a rare occurrence, but is happening regularly It IS due for it's 500 hr maintenance. I am seeing a tiny bit of fluid leakage under the BH joystick station, to the operator floor. I removed the cover, but found nothing unusual. Any suggestions?

 

[Herkypilot]

I'm surprised no one attempted to provide an opinion. I would think you've solved the problem by now, but if not - did you check your HST fluid level?

 

[JerryBuilt]

It got worst, as the hoe would not come back to center or would just pivot hard right, dipstick would slow down, and one outrigger would take 2 minutes to retract. A couple of times an outrigger just extended while I was using the front mounted grapple clearing brush and limbs. Too unsafe to continue on my mountain property. I took the tractor in for service at a local (mostly Massey) tractor repair shop. Several of the O rings and the wipers had failed in the backhoe valve assembly, allowing pressure to build up and activate or block the fluid passages. 7 valves X 2 = 14. The O rings were only a couple bucks, but the wipers ( like a seat that housed the o rings) were a whopping $25 to $27 (25 x 14 =$350) each! I elected to have all replaced for fear the rest were right behind. So after new UDT2 fluid, filters, parts, and a few hundred in labor, for a total of $1400, the tractor and backhoe are running great! Just not happy about the over priced orange fluid ($406) and parts ($450).

 

[Herkypilot]

Wow - that's quite a bit. How old is your tractor? I'm curious how long those O-rings had been in there. I'm glad to hear you have it all taken care of, albeit much lighter in the wallet though. :shocked:

 

[JerryBuilt]

Thanks, It is a 2011!, I wasn't expecting anything this major so soon. I bought it Dec. 2013 with 450 hr. It was a trade in at a Kubota dealer and had 7 months warranty on the tractor, not the implements.
I suspect the owner never changed the fluids? (and I had not either) as he was trading it in on a new tractor. $400 every 200 hours for just the HST fluids, not including the filters is a little steep. I got a decent deal on it and it is a great tractor for this bigger (52 acre) property, with all the clearing and stump removal needed. It does everything I ask of it...... except that one big stump.

 

[Herkypilot]

Well it sounds like you don't use if for commercial use, so it will probably take a year or two to get 200 more hours on it. It's still hard to believe you had O-rings going bad due to the fluid having (what is suspected to have) 450 hours on it.
I bet you are more stubborn then at big stump and it will eventually give way to the mighty Kubota!