L39 Backhoe problems

rbargeron · Apr 14, 2015

To reinforce Stonehaller's comment about piston seal leakage, a friend's "new" backhoe boom cylinder made very little force - it was a low-hour machine but it had not been used for a log period. They found rust inside the barrel - likely from before the cylinder was built. The piston seals were ruined by the rough surface.

korydz · Apr 15, 2015

Thanks for all the help guys. I think it's clear that I have some guck (technical term) in the valves or spools. I have a good friend that is a spectacular HD mechanic that works just down the road that has agreed to tear in to it for me. His tools and experience will all but guarantee results.

I know many of you would encourage me to tackle it myself, and if I had more time and less resources (like the above mentioned conveniently located professional) I'd be inclined to. The feeling of dread of losing a tiny spring or clip buried in one of these assemblies and not even having the experience to realize that I had done so is less than appealing.

Thanks again. I'll let you know how it all turns out.

kubmehc · Apr 15, 2015

It sounds like multiple circuit relief failures. Thinking outside the box, the machine sat at the dealer for a year. The circuit reliefs are a common failure. Were they "borrowed" as failures on other machines occurred and never replaced? Just a thought. Swap the secondary's in the dipper circuit and see if the problem reverses itself

rScotty · Apr 16, 2015

korydz said:
Thanks for all the help guys. I think it's clear that I have some guck (technical term) in the valves or spools. I have a good friend that is a spectacular HD mechanic that works just down the road that has agreed to tear in to it for me. His tools and experience will all but guarantee results.

I know many of you would encourage me to tackle it myself, and if I had more time and less resources (like the above mentioned conveniently located professional) I'd be inclined to. The feeling of dread of losing a tiny spring or clip buried in one of these assemblies and not even having the experience to realize that I had done so is less than appealing.

Thanks again. I'll let you know how it all turns out.

Please do let us know how it turns out. It really does sound like either the 3pt/BH levers or else someone has messed with it and not put it back together right. A pro should be able to find it....and his work will be interesting.

I think you will be satisfied once it is working right. The L39 is a popular model for good reason.
Our M59 is similar in design, and the BH has a ridiculous amount of power. One has to be careful with the BH levers to keep from throwing the whole tractor around. One get the feeling that if it got hold of something solid the BH could pick up the whole tractor at arm's length and shake it like a dog with a bone. It's a good thing that the control levers are very progressive and sensitive. To my surprise, they are more sensitive than the ones on our JD310.
Good luck, hope the dealer helps out too.
rScotty

cmiller0488 · Dec 11, 2022

korydz said:
Thanks for all the help guys. I think it's clear that I have some guck (technical term) in the valves or spools. I have a good friend that is a spectacular HD mechanic that works just down the road that has agreed to tear in to it for me. His tools and experience will all but guarantee results.

I know many of you would encourage me to tackle it myself, and if I had more time and less resources (like the above mentioned conveniently located professional) I'd be inclined to. The feeling of dread of losing a tiny spring or clip buried in one of these assemblies and not even having the experience to realize that I had done so is less than appealing.

Thanks again. I'll let you know how it all turns out.

I'm reviving this dead post.

Could you please give closure and tell us what the issue was that you found?

Thanks