BH77 Hydraulic Concerns

[minthral]

You are getting close to understanding.

The upper right port is pump pressure OUT to auxiliary equipment.
The bottom center port is low pressure tank return from auxiliary equipment. It goes straight to the sump.
The upper left is high pressure IN from the auxiliary equipment. It powers the 3pt.

Dan

Oh ok so in that case I got it backwards... so on mine the loop is loader > third function > remotes > backhoe. No idea where the 3 point is as I don't see any of these hoses. The upper left port hose goes to backhoe (as a return).

 

[TheOldHokie]

Oh ok so in that case I got it backwards... so on mine the loop is loader > third function > remotes > backhoe. No idea where the 3 point is as I don't see any of these hoses. The upper left port hose goes to backhoe (as a return).

Yes - you had it backwards, which is easy to do. The hose going from the back hoe vlave to the hydraulic block is feeding the 3pt. That port on the hydraulic block connects to a pipe that goes up the right side of the tractor and then into the 3pt valve.

Dan

 

[Kenhwy61]

I know this is an older thread but quite relevant to my problem and I am hoping one the tractor gurus who posted here may be able to help. I have a 2023 LX2610 with a BH77 and the third function valve installed. The problem is the BH valve body keeps leaking badly. It has been back to the dealer 4 times in 80 hours. The first three times the dealer replaced failed seals and the last time it leaked it was found the cast iron BH valve body actually broke apart. So this they installed a new valve body but I was using the tractor today and now the new valve body is leaking just as bad as the old one. I believe the valve body is being way over pressurized somehow. After reading this thread I think the 3rd function is possibly plumbed wrong. This how the BH lines are plumbed to the best of my knowledge. The line comes out of the pump and flows into the BH then comes out of the BH and flows into the 3rd function port labeled "T". This 3rd function valve is located up near the loader and runs a 4 in 1 bucket. From the 3rd function port labeled "P" the other line appears to be the return line and runs back to into the top of the case. There are two other lines attached to the 3rd function valve that I think go to the bucket cylinder. Does anybody know what the T and P stamped into the 3rd function body mean and if this is plumbed correctly?
Thank you

 

[TheOldHokie]

I know this is an older thread but quite relevant to my problem and I am hoping one the tractor gurus who posted here may be able to help. I have a 2023 LX2610 with a BH77 and the third function valve installed. The problem is the BH valve body keeps leaking badly. It has been back to the dealer 4 times in 80 hours. The first three times the dealer replaced failed seals and the last time it leaked it was found the cast iron BH valve body actually broke apart. So this they installed a new valve body but I was using the tractor today and now the new valve body is leaking just as bad as the old one. I believe the valve body is being way over pressurized somehow. After reading this thread I think the 3rd function is possibly plumbed wrong. This how the BH lines are plumbed to the best of my knowledge. The line comes out of the pump and flows into the BH then comes out of the BH and flows into the 3rd function port labeled "T". This 3rd function valve is located up near the loader and runs a 4 in 1 bucket. From the 3rd function port labeled "P" the other line appears to be the return line and runs back to into the top of the case. There are two other lines attached to the 3rd function valve that I think go to the bucket cylinder. Does anybody know what the T and P stamped into the 3rd function body mean and if this is plumbed correctly?
Thank you

Those failures sound like the backhoe valve may be in the wrong place in the circuit. Your description of the plumbing is definitly incorrect.

Flow should be:

PUMP->LOADER->3RD FUNCTION'->BACKHOE

Post a couple pictures of your plumbing so we can sort out what you actually have. Something is definitly wrong.

Dan

 

[TheOldHokie]

Here is the factory 3rd function for your tractor. It is mounted under the floorboards. Is this what you have or do you have something else?

Dan

 

[TheOldHokie]

One more question - do you also have rear remotes on the tractor?

Dan

 

[beckmurph]

I know this is an older thread but quite relevant to my problem and I am hoping one the tractor gurus who posted here may be able to help. I have a 2023 LX2610 with a BH77 and the third function valve installed. The problem is the BH valve body keeps leaking badly. It has been back to the dealer 4 times in 80 hours. The first three times the dealer replaced failed seals and the last time it leaked it was found the cast iron BH valve body actually broke apart. So this they installed a new valve body but I was using the tractor today and now the new valve body is leaking just as bad as the old one. I believe the valve body is being way over pressurized somehow. After reading this thread I think the 3rd function is possibly plumbed wrong. This how the BH lines are plumbed to the best of my knowledge. The line comes out of the pump and flows into the BH then comes out of the BH and flows into the 3rd function port labeled "T". This 3rd function valve is located up near the loader and runs a 4 in 1 bucket. From the 3rd function port labeled "P" the other line appears to be the return line and runs back to into the top of the case. There are two other lines attached to the 3rd function valve that I think go to the bucket cylinder. Does anybody know what the T and P stamped into the 3rd function body mean and if this is plumbed correctly?
Thank you

I think it is plumbed incorrectly.

3rd function lines are reversed.
P pressure comes from backhoe.
T is return to tank.

 

[TheOldHokie]

This how the BH lines are plumbed to the best of my knowledge. The line comes out of the pump and flows into the BH then comes out of the BH and flows into the 3rd function port labeled "T". This 3rd function valve is located up near the loader and runs a 4 in 1 bucket. From the 3rd function port labeled "P" the other line appears to be the return line and runs back to into the top of the case.
Thank you

This has been bugging the crap out of me. I think your currwnt plumbing is correct but your description is simply backwards:

The flow starts at the loader valve on the side of the transmission, goes to the P port on the 3rd function, out the T port to the backhoe and then returns to the top of the transmission.

If so that would be the proper hookup which begs the question of what is causing the problems with the backhoe valve.

The possibility that jumps to mind is the 3pt control valve. You MUST keep that lever in the full down position whenever the backhoe is connected. If you raise it you will over presdure the return port on the backhoe and blown seals are the first thing to go.

Dan

 

[TheOldHokie]

I think it is plumbed incorrectly.

3rd function lines are reversed.
P pressure comes from backhoe.
T is return to tank.

See my post just below yours.

I think the plumbing is probably correct and his description is backwards.

Pressure (P) is coming from PB on loader valve and T is carrying that pressure over to backhoe. That's as it should be.

 

[beckmurph]

See my post just below yours.

I think the plumbing is probably correct and his description is backwards.

Pressure (P) is coming from PB on loader valve and T is carrying that pressure over to backhoe. That's as it should be.

 

[TheOldHokie]

View attachment 142329

Three things worth noting:

1. The BH77 doess not have a power beyond cabability and must NEVER supply pressure to any downstream valve.
2. Thats the Landpride kit not the OEM kit.
3. The valves used in both kits would still work fine if inlet and outlet were actually reversed.

Now if you can explain how a BH77 can work with LX factory rear remotes installed between it and the 3pt I am all ears.

Dan

 

[Kenhwy61]

Three things worth noting:

1. The BH77 doess not have a power beyond cabability and must NEVER supply pressure to any downstream valve.
2. Thats the Landpride kit not the OEM kit.
3. The valves used in both kits would still work fine if inlet and outlet were actually reversed.

Now if you can explain how a BH77 can work with LX factory rear remotes installed between it and the 3pt I am all ears.

Dan

Thank you for all the replies. I will do some more investigating and take some photos. I did notice that the lines from the BH definitely jerk when the 3rd function is activated especially if the 3rd function cylinder is deadheaded. I will try to post again soon.

 

[TheOldHokie]

Thank you for all the replies. I will do some more investigating and take some photos. I did notice that the lines from the BH definitely jerk when the 3rd function is activated especially if the 3rd function cylinder is deadheaded. I will try to post again soon.

Simple easy to answer question - do you have rear remotes on the tractor and if so are thèy OEM?

Dan

 

[Kenhwy61]

Simple easy to answer question - do you have rear remotes on the tractor and if so are thèy OEM?

Dan

There are no rear remotes and the 3pt level is in the lowest position. I double checked the plumbing. The line with the blue dustcover comes out of the pump and into the BH valve body. It then goes out via the line with the red dust cover and goes to the T port on the 3rd function valve. Then there is a line from the P port that returns to the top of the case. I attached some photos. Thank you for the help.

Simple easy to answer question - do you have rear remotes on the tractor and if so are thèy OEM?

Dan

There are no rear remotes and the 3pt lever is all the down. I doublechecked the plumbing. The line with the blue dust cover I labled with a B at the ends. It runs out of the pump, through the BH disconnect coupler and into the BH valve body. It then the runs from the valve body through the other BH disconnect coupler line with the red dust cover to the 3rd function valve T port. From there another line runs from the P port back into the top of the case. Thanks for all the help.

 

[TheOldHokie]

There are no rear remotes and the 3pt level is in the lowest position. I double checked the plumbing. The line with the blue dustcover comes out of the pump and into the BH valve body. It then goes out via the line with the red dust cover and goes to the T port on the 3rd function valve. Then there is a line from the P port that returns to the top of the case. I attached some photos. Thank you for the help.

There are no rear remotes and the 3pt lever is all the down. I doublechecked the plumbing. The line with the blue dust cover I labled with a B at the ends. It runs out of the pump, through the BH disconnect coupler and into the BH valve body. It then the runs from the valve body through the other BH disconnect coupler line with the red dust cover to the 3rd function valve T port. From there another line runs from the P port back into the top of the case. Thanks for all the help.

OK. I see no blue dust cover in those pictures. I am beginning to think it may well be plumbed wrong but if connected as you describe its totally screwed up.

Here is the pump (lower left corner) and delivery line on your tractor. Where is the hose that goes to the backhoe connected?

Dan

 

[Kenhwy61]

There are no rear remotes and the 3pt level is in the lowest position. I double checked the plumbing. The line with the blue dustcover comes out of the pump and into the BH valve body. It then goes out via the line with the red dust cover and goes to the T port on the 3rd function valve. Then there is a line from the P port that returns to the top of the case. I attached some photos. Thank you for the help.

There are no rear remotes and the 3pt lever is all the down. I doublechecked the plumbing. The line with the blue dust cover I labled with a B at the ends. It runs out of the pump, through the BH disconnect coupler and into the BH valve body. It then the runs from the valve body through the other BH disconnect coupler line with the red dust cover to the 3rd function valve T port. From there another line runs from the P port back into the top of the case. Thanks for all the help.

Sorry for the duplicate posts. I am tr

 

[Kenhwy61]

Sorry for the duplicate posts. I am tr

Here is another photo I thought uploaded. The fitting in the photo marked with the B goes to BH valve body port also marked with a B as shown in one the other photos. It then comes out of the valve body fitting marked with a R and goes to the T port on the 3rd function. I am sorry for the confusion. I may not be sure in my terminology. I was thinking the pump pressure outlet is where lines 010 and 090 connect on the diagram you posted. I hope this photo helps clarify.

 

[TheOldHokie]

Here is another photo I thought uploaded. The fitting in the photo marked with the B goes to BH valve body port also marked with a B as shown in one the other photos. It then comes out of the valve body fitting marked with a R and goes to the T port on the 3rd function. I am sorry for the confusion. I may not be sure in my terminology. I was thinking the pump pressure outlet is where lines 010 and 090 connect on the diagram you posted. I hope this photo helps clarify.

BINGO - I think we are getting close and no need to apologize

I suspect whoever installed the 3rd function did not understand the circuit and put it on the wtong side of the backhoe.

The pipe (B) in this picture would go to the backoe if you did not have the third function. With a third function that should go to the P port on the third function and the T port on the third function then goes yo the backhoe. The backhoe return then goes to the top of the transmission (3pt).

That tractor needs to go back to the dealer that installed the 3rd function and/or backhoe. Tell them you think you have identified the problem and they need to fix it at their expense.because they screwed it up. I would also ask for a full refund of any expenses you paid trying to get it fixed the previous 4 times.

Dan

 

[Kenhwy61]

BINGO - I think we are getting close and no need to apologize

I suspect whoever installed the 3rd function did not understand the circuit and put it on the wtong side of the backhoe.

The pipe (B) in this picture would go to the backoe if you did not have the third function. With a third function that should go to the P port on the third function and the T port on the third function then goes yo the backhoe. The backhoe return then goes to the top of the transmission (3pt).

That tractor needs to go back to the dealer that installed the 3rd function and/or backhoe. Tell them you think you have identified the problem and they need to fix it at their expense.because they screwed it up. I would also ask for a full refund of any expenses you paid trying to get it fixed the previous 4 times.

Dan

Dan thank you very much. If you don't mind I would like to show them your post. I think your expertise should be quite useful to the techs at the dealership. The good news is the dealer has been responsive and quick to pick up the tractor for service and everything has been covered under warranty.
Thanks again

 

[TheOldHokie]

Dan thank you very much. If you don't mind I would like to show them your post. I think your expertise should be quite useful to the techs at the dealership. The good news is the dealer has been responsive and quick to pick up the tractor for service and everything has been covered under warranty.
Thanks again

Show them this post and picture. Its how the backhoe is installed when there is no 3rd function.

When the third function is added it replaces pipe number 1.

I think yours is installed in place of pipe number 2. If you do that everytime you operate the 3rd function it over pressures the low pressure tank port on the backhoe valve and damages the valve.

Dan