sudden loss of hydraulic function

[netspyder]

so, there i was this morning, trying to dig an outhouse with my 3-point post hole digger... and on the 4th attempt it actually started digging but then i lost the ability to lift the 3 point or FEL - no response to the spools on either of those. all the functions were working fine prior to this - the air intake light was on (but i'm guessing that's humidity clinging to the filter because i've had to park it outside for a few weeks - it goes out after it runs for a while and dries out) but other than that it was working and sounded fine.

i do hear what sounds like a pressure relief valve - hissing doesn't seem like quite the right description - from under the seat. the only thing right there is the 3 point speed knob. is there a relif valve on that? i don't see any leaks underneath and the hydraulic level is good. steering and transmission seem fine.

this is a 1998 L3010HST. i have the service manuals downloaded but they don't seem to have very good exploded views. any ideas for things to check? i don't have a pressure gauge yet. i looked at the parts diagrams on the kubota site but i'm not sure what i'm looking for.

 

[North Idaho Wolfman]

Disconnect and reconnect any quick connects on the loader.
If the hydraulics on the BH run off of the the tractor hydraulic system disconnect it.

 

[netspyder]

as soon as i posted this i found the relief valve checking and adjusting section. guess i'm going to need a gauge.

 

[netspyder]

Disconnect and reconnect any quick connects on the loader.

i will give that a try before i start tearing it apart, thanks

 

[TheOldHokie]

i will give that a try before i start tearing it apart, thanks

Dont start tearing things apart. The relief valve "hissing" means the system is at max pressure. You dont need to adjust pressure.

Something is preventing flow through the control valves. I will bet the loader bucket curl and dump still works.

Check that all control levers are in the neutral position and that all quick connects are fully seated. Pay particular attention to any rear remote valves.

Dan

 

[Russell King]

If the backhoe was removed then you need to check the loop connection that must be done for the hydraulic system to work. That is usually the culprit and disconnecting the disconnect and redoing it usually fixes the problem.

 

[PoTreeBoy]

I haven't thought this through completely, but it doesn't require a gauge. Try lowering your 3ph a little and see if the hissing stops and the loader starts working.

If it does, 6 people will tell you the permanent fix.