Backhoe Hydraulic circuit for power beyond with third function kit on Grand L60

[100 td]

Check your email

 

[100 td]

To make it short(I'm a slow typer) By having the third function after the backhoe, whenever it is used it can pressure spike the backhoe valve and blow seals or crack a casting. The same goes for remotes or 3pt. However, you are unlikely to use 3pt or remotes when the hoe is attached, but the third function is a different story. The third function should be installed before the backhoe. I expect the backhoe valve block will be cracked or have a blown oring/s.

 

[mljenkins]

To make it short(I'm a slow typer) By having the third function after the backhoe, whenever it is used it can pressure spike the backhoe valve and blow seals or crack a casting. The same goes for remotes or 3pt. However, you are unlikely to use 3pt or remotes when the hoe is attached, but the third function is a different story. The third function should be installed before the backhoe. I expect the backhoe valve block will be cracked or have a blown oring/s.

The BH92 manual states "It is necessary to have the backhoe detached when using rear remotes, the 3-point hitch, or any other valves that are downstream of the backhoe valve. Failure to do this may cause the exceeding allowable back pressure to break the seal or case of he backhoe valve."

So I think their manual pretty much clearly states the plumbing is wrong as you state.

I just called my dealer and left a message with them and sent them an email explaining what I found with the circuit. We'll see what they say. Hopefully they will make things right.

 

[mljenkins]

I wanted to finally take the time to update the thread here. My dealer did get the tractor back to me after a week or two in the shop. They had someone from Kubota look at it and they agreed the plumbing was incorrect. The third function has to be before the backhoe in the circuit or it can cause back pressure on the backhoe valve block.

When I got the tractor back, the I tested the backhoe for a few minutes (at around 2200 rpm I believe) by using the various functions against a stump to create load on the system. I did not notice any leaks, but I had to drop the backhoe the same day to get my cutter on to get my mowing done before fall set in. I have since had to grade my driveway so I haven't had a chance to put the backhoe back on and give it a through test.

When got the tractor back, I think my third function controls are now reversed. Not a big deal since I can simply swap the hoses on the front, but I am curious why they had to swap those hoses. I don't know if the third function has a port that is supposed to be input and one for output. If anyone knows please let me know.

Nonetheless, I traced the hoses and things look correct now, at least with regards to where the backhoe and third function are in relationship to each other in the circuit. I would definitely encourage anyone that gets a new tractor to check the hydraulic plumbing before using it much to make sure your dealer gets things plumbed correctly, especially if you have a power beyond/backhoe kit installed.

 

[Fallon]

I wanted to finally take the time to update the thread here. My dealer did get the tractor back to me after a week or two in the shop. They had someone from Kubota look at it and they agreed the plumbing was incorrect. The third function has to be before the backhoe in the circuit or it can cause back pressure on the backhoe valve block.

When I got the tractor back, the I tested the backhoe for a few minutes (at around 2200 rpm I believe) by using the various functions against a stump to create load on the system. I did not notice any leaks, but I had to drop the backhoe the same day to get my cutter on to get my mowing done before fall set in. I have since had to grade my driveway so I haven't had a chance to put the backhoe back on and give it a through test.

When got the tractor back, I think my third function controls are now reversed. Not a big deal since I can simply swap the hoses on the front, but I am curious why they had to swap those hoses. I don't know if the third function has a port that is supposed to be input and one for output. If anyone knows please let me know.

Nonetheless, I traced the hoses and things look correct now, at least with regards to where the backhoe and third function are in relationship to each other in the circuit. I would definitely encourage anyone that gets a new tractor to check the hydraulic plumbing before using it much to make sure your dealer gets things plumbed correctly, especially if you have a power beyond/backhoe kit installed.

3rd function polarity can be rather arbitrary. Loader controls are very standardized & have polarity due to float & regen. But the 3rd function & rear remotes are arbitrary.

My 3rd function has 1 male & 1 female flat face connector on it so polarity always stays correct when I put connectors on an impliment. I have to color code or just guess for my rear remotes. No big deal if I guess wrong other than needing to re-learn controls or swap hoses if it's really odd.