New L3560HST-LE with BH92 : possible problem with hydraulics on BH92

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Well... my son and I finally sprang for the L3560-LE (HST) with the 805 loader. It has a nice combination of features and heft and price. He got a good-sized grapple and logging winch for his woods-work, I got the BH92 for trenches. It was a struggle getting all the bits together from our regional (upstate NY) dealer even though they were trading around 3 franchises. It took about a month to get a configured unit. But it is mostly here now (waiting on a smaller bucket and one more set of wheel weights.)

It has been in the woods for over a week but is now on my place (10 miles away) and I have been experimenting with the backhoe. My son and I are both complete newbies with tractors. I have rented small, medium and larger tracked excavators over the years for some trench and drainage work but am still safely labelled a "newbie".

I noticed yesterday a possible issue with the backhoe hydraulics. Hoping for some thoughts.

When I am curling the bucket in I can't get the boom-lifter to engage until I stop the bucket curl. If I start easy with the boom-lift and use the separate joystick to engage a bucket-curl-in the bucket seems to grab all the hydraulics and the boom-life just stops. If I hold the boom-lift joystick and then halt the curl-in operation the lifter jumps on and jolts things pretty significantly. Since the curl and crowd operations dynamically change the digging depth the option of boom-lifting seems crucial - no?

This happened while running at about 2000 rpm and also when I bumped up to 2500 for some more oomph: I cannot combine the two separate hydraulic actions: boom-life + bucket-curl-in.

I found a thread here yesterday (now can't find it) with a similar concern about running both hydraulic lines at once on the BH92. The person posting eventually had a dealer involved and they found weak hydraulic pressure in one side and had to do some repair-replacement. I will call my dealer about this since the machine is very new - 15 hours on it and maybe 3 hours on the backhoe. But I thought it better to ask here first and get some sense of whether this is normal or a likely problem I can ask for warranty service with confidence.

thanks
Daryl
 

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
280
55
28
Arkansas, US
Its open center hydraulics. The different controls have more priority in the lineup. You have to get better at feathering otherwise it cuts (steals) all the flow. If one seems really weak it could use a relief valve tweak. The different valves have varying flow restrictions on them too.
 
Last edited:

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Its open center hydraulics. The different controls have more priority in the lineup. You have to get better at feathering otherwise it cuts (steals) all the flow. If one seems really weak it could use a relief valve tweak. The different valves have varying flow restrictions on them too.
Thanks. I figured the two systems were fighting over access to the hydraulics in some way - it just seemed unusual that when I combined systems from the two joysticks in other ways I did not get one just shutting down the other one like this. Even if I am super-light-touch on the boom-lift and go super light on the bucket curl the boom lift just cuts out.

I know I have to get better at feathering - though maybe I don't know what that means ! I thought feathering was using a very light touch on the control and by doing that calling for only a fraction of the max hydraulics... and I have tried that - working the machine with the bucket in the air and trying different combinations like I mentioned above. I have been digging around and found some places that talk about feathering as if it is a super-fast on-off action on the joystick. I can try that I guess.

Obviously a "newbie" on a new tractor means that some sort of operator error most likely is the explanation ! But I do read about new machines coming mis-configured and since I am on warranty would want to approach the dealer if I had a sense of something being wrong -- so the dealer does not just assume I am not feathering right and sends me back to practice!

Any suggestions for what would I look for here to get any sense if something is actually wrong with the hydraulics?

thanks
 

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
280
55
28
Arkansas, US
Try all the functions one at a time. They should be strong enough to move the machine at least few inches at mid rpm. Left stick is boom lift and swing. Right stick is dipper, and bucket. Now when they are used in conjunction left, right stick you will just have to find the sweet spot to get two actions. Now if any single function fails to move the machine, or feels exceptionally weak, that individual valve could use a pressure adjustment. If you feel a particular lever has less throw, pop off the rubber boot and make sure it does not hit the cover sheet metal in its travel.

Do you have a third function? It can cause issues if hooked up incorrectly.
 

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Try all the functions one at a time. They should be strong enough to move the machine at least few inches at mid rpm. Left stick is boom lift and swing. Right stick is dipper, and bucket. Now when they are used in conjunction left, right stick you will just have to find the sweet spot to get two actions. Now if any single function fails to move the machine, or feels exceptionally weak, that individual valve could use a pressure adjustment. If you feel a particular lever has less throw, pop off the rubber boot and make sure it does not hit the cover sheet metal in its travel.

Do you have a third function? It can cause issues if hooked up incorrectly.
Thanks for the follow-up.... and encouragement. I WAS able to get a combined boom-life with bucket-curl today with very subtle action - I guess thats why they call it feathering. Clearly it will take some time. The boom lifter sounds a little noisy-weird, in a sort of hissy-whiney way, at times but I don't know what to compare that to. I DO have a third function connected up on the backhoe to manage a grapple. It needs to be activated by switch and has not been on when I am backhoe'ing... but it is part of the hydraulics I suppose.
 

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
280
55
28
Arkansas, US
The differing valve sounds are more than likely the different flow restrictors.(I would say normal) I am suspect of the third function. They can wreck the backhoe seals if not configured in the right order. Pictures of the lines above three point rock shaft by chance?
 

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Hmmm... I hope this is what you want... not sure what a "rock shaft" is!
On the right, looking forward behind the backhoe seat which is tilted...
IMG_20210507_161358.jpg
 

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
280
55
28
Arkansas, US
Hmmm... I hope this is what you want... not sure what a "rock shaft" is!
On the right, looking forward behind the backhoe seat which is tilted...
View attachment 59477
The rock shaft is the splined top shaft that raises the lift. The two 90’ coming off the top there, where do they lead? The right most one goes the the backhoe inlet.(bracket with female quick disconnect) and the other goes to the longer line(male). If you have the third function it gets fed first before the backhoe. The power beyond from the third function feeds the backhoe inlet. So follow those lines and make sure it is routed correctly. It’s hard to tell from the pic.
 

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Thanks again... here is an update with some more hydraulic-line tracing and some pics but I will get back out there and look some more.

Right now my 3rd Function (grapple) is disconnected. Loader is up front.

The two 90 elbows coming off the top in front of that rock shaft go forward under the seat and I can't get much sense of where they go.
IMG_20210508_120900.jpg


I got a closer picture which is attached. The two lines with quick-connects come forward from the Backhoe and do junction with some sort of switch/valve mounted down low under a cover with "Not a Step" label to the right of the seat - they share that valve with the lines from the 3rd Function. I was able to trace these BH lines and 3F lines. Picture attached {the BH lines come off of the metal hoses coming out on the left and right, the two coming out toward the view, with the black protective covers, go forward up to the 3rd Function.

I will look it over some more. Right now I still have more questions which reflect my ignorance I know!

Thinking about the general scheme I realize that the "boom lift" function is probably putting the most demand on the hydraulics - lifting, what? 1500 pounds of arm+bucket? So if the 3rd function is taking some percentage away from the overall hydraulic capacity it would likely affect that one function the most... but if the 3rd Function is DC'ed how is it having any dynamic effect on things at all?
 

Attachments

Last edited:

Dander53

New member

Equipment
L3560HST-LE, BH92, LA805
Mar 20, 2021
6
0
1
Upstate NY
Thanks again... here is an update with some more hydraulic-line tracing and some pics but I will get back out there and look some more.

Right now my 3rd Function (grapple) is disconnected. Loader is up front.

The two 90 elbows coming off the top in front of that rock shaft go forward under the seat and I can't get much sense of where they go. View attachment 59531

I got a closer picture which is attached. The two lines with quick-connects come forward from the Backhoe and do junction with some sort of switch/valve mounted down low under a cover with "Not a Step" label to the right of the seat - they share that valve with the lines from the 3rd Function. I was able to trace these BH lines and 3F lines. Picture attached {the BH lines come off of the metal hoses coming out on the left and right, the two coming out toward the view, with the black protective covers, go forward up to the 3rd Function.

I will look it over some more. Right now I still have more questions which reflect my ignorance I know!

Thinking about the general scheme I realize that the "boom lift" function is probably putting the most demand on the hydraulics - lifting, what? 1500 pounds of arm+bucket? So if the 3rd function is taking some percentage away from the overall hydraulic capacity it would likely affect that one function the most... but if the 3rd Function is DC'ed how is it having any dynamic effect on things at all?
------------------------------------------------------------------------------------
MORE LINE TRACING RESULTS

I am almost certain that the RIGHT-most 90 coming off the top goes forward to the "valve" that serves the 3rd Function and also then has a return to the BH and then the BH lines eventually loop back to the LEFT-most 90 coming off the top. This seems not to match what you expected for the right-most 90.
 
Last edited:

kubotafreak

Active member

Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Sep 20, 2018
280
55
28
Arkansas, US
Yes how you described is right, the right most from the rear goes forward to the third function(orange inlet P) and the return (green PB) feeds the backhoe quick connect female. The return male backhoe completes the circuit and goes to the left most above rock shaft. Ignore the gray. It is for a different third function with direct to tank. The colors can be swapped around as the green and orange hose are about the same length. How they connect need to be in this order otherwise you can have problems. On the lower front of the third function the green should be the front most of the three ports, and the orange inlet is the rear most of the three ports(port on the gray bracket behind front right wheel.
 

Attachments