M59 backhoe boom dead

[Shawnba67]

So i just bought a 2012 M59. On test driving everything seemed to function as should minus a few leaks. On delivery the boom is pretty much dead. It will jerk a bit then go smoothly for a moment then you can hear the fluid flow stop and the boom just falls outward. It took a couple dozen tries to get boom back up into its locked position. Would give up inches from "home".
The guy that delivered it said it loaded fine, but was doing this on arrival.
So this is what I do know it's not the cylinder needing repacked. That $200 would be nice to have back. Lol
I have reprint WSM and Parts books but they do not make sense the way I would like.
Ideas?
If anyone is following my saga I got the glow plugs sorted out. $9 push button switch on relay control. Beats the snot out of a $1200 elec module which is where that ground was supposed to come from.

 

[GreensvilleJay]

curious, do ALL the other BH levers work as they should? stabs, turn, bucket, ???
If JUST the boom, then it'd be in THAT section of the 'spool valve assembly'.

 

[mikester]

To start, check that the diverter valves are pushed all the way in.

Check your hydraulic fluid levels.

 

[Shawnba67]

The parts manual shows several O rings in the spool valve assembly. Are these a have to be from Kubota thing or just a same size/grade o ring will be fine?

 

[GreensvilleJay]

Please order them from Kubota ! Dealer may have in stock !!! That way you get parts that WILL 100% work properly. Orings from hardware store are 'questionable' at best.
You'll be 'upset' if you go cheap and then find out they economy orings fail and then have to spend another day repairing the repair.....

 

[TheOldHokie]

The parts manual shows several O rings in the spool valve assembly. Are these a have to be from Kubota thing or just a same size/grade o ring will be fine?

I think uou need to run a few diagnostics before you start throwing parts.

Based on the problem description I would be wondering about the port relief valves on the boom....

Dan

 

[Smokeydog]

If you search this forum or TBN, you’ll find similar issues with sporadic loss of M59 backhoe function. Better explanation than I could give. More often with swing. Have experienced loss of boom down power but not up. Others have found cleaning and O-ring replacement a remedy. Spec of dirt or piece of O-ring can jam the relief and cause loss of function. Fortunately loss has been sporadic and heals quickly so far.

 

[Shawnba67]

Well I tore into the valve block and it appears it was just some spider sh!@ in the relief valve. The bottom one would bind up occasionally cleaned all up and reassembled and she seems to be alive!!!

 

[TheOldHokie]

Well I tore into the valve block and it appears it was just some spider sh!@ in the relief valve. The bottom one would bind up occasionally cleaned all up and reassembled and she seems to be alive!!!

Simple and cheap

Dan

 

[Smokeydog]

Well I tore into the valve block and it appears it was just some spider sh!@ in the relief valve. The bottom one would bind up occasionally cleaned all up and reassembled and she seems to be alive!!!

Replace O-rings or just clean? Pictures would help.