Hydraulic rear remote problem

[Russell King]

Back in the summer of 2023 I installed a rear remote valve on my L185. I really never used the tractor for any length of time since then until last weekend. I was shredding for about two hours and noticed the tractor was struggling a bit with the load.

I touched the hydraulic pump and it was pretty hot and so was the rear remote valve.

There is a high pitched noise in the rear remote valve that I assume is something limiting the flow of hydraulic fluid through the valve.

The valve is a Bucher valve 12 GPM version that has the numbers 19-4 831000011 cast near the T port

The P port is connected to the pump out put. The power beyond sleeve was installed and labeled and is routed to the three point valve feed. The T port dumps to the top of the transmission case.

All hydraulics work correctly. Rear remotes move both directions and go into relief at end of their travel. The three point hitch moves up and down and will go into relief when lifting the shredder off the ground when it reaches top of movement.

I hear a noise constantly from the rear remote valve except when I adjust a cylinder or adjust the 3PH. The noise goes away but returns when lever is released.

I am going to take the valve out of the circuit and run it again if I can get some caps and connectors tomorrow morning. I plan to connect the hoses from P and PB together and cap off the valve fittings.

I just have no idea how to fix the valve if the problem is in the valve itself. So the question is how to resolve an issue with the valve limiting the flow and increasing the pressure on the pump?

I will post pictures of the system and valve in a second post

 

[Russell King]

Here is the numbers on the valve (sorry it is upside down)

and the connections to the valve power beyond

 

[Russell King]

Connection to the tractor
left side goes to power in (P)
right side to power beyond (unknown symbol on valve)
center is tank return (T)

Here is the power beyond port on the valve. I think the symbol may be a B for Bucher?

 

[Russell King]

Please make suggestions on how to troubleshoot the issue and also how to fix the valve if that is the issue.

 

[TheOldHokie]

Please make suggestions on how to troubleshoot the issue and also how to fix the valve if that is the issue.

Install a tee on the power beyond port and measure pressure with all remotes and 3pt in neutral.

Dan

 

[Russell King]

@TheOldHokie - thank you for the suggestion.

Well here is what I found out today

I put the tee with gauge on the power beyond fitting and ran the tractor at PTO speed (around 3000 RPM) and there was no pressure until I raised the three point and pressure climbed to 1500 PSI.

The implement was the shredder and it was lifted completely off of the ground.

I then moved the guage to the input (P) side of the valve and got the same results.

I capped off the valve input and power beyond and connected the two hoses together so the valve was completely out of the system.

When I started the tractor I noticed a noise in the hose that sounded like a lot bubbles. So I checked the hydraulic fluid level and it was low. So I put in about 2.5 gallons before it started running out of the full port. I started the tractor and it sounded better but there was still some cavitation type noise through the hoses.

I then shredded for a couple of hours and came up with the same results- a hot hydraulic system and a seemingly overloaded engine.

To me the tests and results eliminate the valve as the problem.

I was surprised at how hot the hydraulic system got with nothing loading it. When setting the brake there is a metal loop to pull up that is attached to the transmission case, it was too hot to pull up with my bare finger.

I will not be back at the tractor until the weekend and have a couple of things to try:
1) Listen to the pump to see what it sounds like.
2) Remove the hydraulic splitter block I installed and reinstall the original so the tractor is back to the original configuration. Run it and see what happens
3) Take the pump off and disassemble it to see what it looks like.
.
I will have to replace the shaft seal on the pump so may not be able to get that this week. If the pump is damaged I don’t know if I will be able to get a replacement. And if it was damaged would it make pressure?

I could not comfortably keep my bare hand on any of the steel parts of the hydraulic system for more than a second or two. I don’t recall if I ever touched it before but I don’t recall that the parking brake finger loop was ever even warm. How hot is a normally operating hydraulic system?

Any suggestions on what to look at?

 

[TheOldHokie]

@TheOldHokie - thank you for the suggestion.

Well here is what I found out today

I put the tee with gauge on the power beyond fitting and ran the tractor at PTO speed (around 3000 RPM) and there was no pressure until I raised the three point and pressure climbed to 1500 PSI.

The implement was the shredder and it was lifted completely off of the ground.

I then moved the guage to the input (P) side of the valve and got the same results.

I capped off the valve input and power beyond and connected the two hoses together so the valve was completely out of the system.

When I started the tractor I noticed a noise in the hose that sounded like a lot bubbles. So I checked the hydraulic fluid level and it was low. So I put in about 2.5 gallons before it started running out of the full port. I started the tractor and it sounded better but there was still some cavitation type noise through the hoses.

I then shredded for a couple of hours and came up with the same results- a hot hydraulic system and a seemingly overloaded engine.

To me the tests and results eliminate the valve as the problem.

I was surprised at how hot the hydraulic system got with nothing loading it. When setting the brake there is a metal loop to pull up that is attached to the transmission case, it was too hot to pull up with my bare finger.

I will not be back at the tractor until the weekend and have a couple of things to try:
1) Listen to the pump to see what it sounds like.
2) Remove the hydraulic splitter block I installed and reinstall the original so the tractor is back to the original configuration. Run it and see what happens
3) Take the pump off and disassemble it to see what it looks like.
.
I will have to replace the shaft seal on the pump so may not be able to get that this week. If the pump is damaged I don’t know if I will be able to get a replacement. And if it was damaged would it make pressure?

I could not comfortably keep my bare hand on any of the steel parts of the hydraulic system for more than a second or two. I don’t recall if I ever touched it before but I don’t recall that the parking brake finger loop was ever even warm. How hot is a normally operating hydraulic system?

Any suggestions on what to look at?

The pressures are correct so the remotes seem to be operating fine.

Hydraulic oil csn easily hIt 60C (140F) which is scalding hot. You cant keep your hand on a surface that hot without suffering burns. Not sure I see a problem there.

O would not even think about taking the pump apart. Thats just asking for ttoublr.

Dan

 

[Russell King]

The engine was never struggling nor getting hot before the installation and now it is. The transmission case was never hot before.

Those are the issues I have now.

I will try to identify what is causing the heating of the hydraulic fluid and currently the only things that would create heat are the pump and the change in plumbing.

 

[North Idaho Wolfman]

Connection to the tractor
left side goes to power in (P)
right side to power beyond (unknown symbol on valve)
center is tank return (T)

View attachment 122237

Please clarify that when you say right and left you mean in relation to the picture not in relation to the tractor?

 

[TheOldHokie]

The engine was never struggling nor getting hot before the installation and now it is. The transmission case was never hot before.

Those are the issues I have now.

I will try to identify what is causing the heating of the hydraulic fluid and currently the only things that would create heat are the pump and the change in plumbing.

Then put the OEM outlet cover bsck on and see if the heating problem goes away before tearing the pump spart.

You might also check the fit on the replacement diverter block. You hxve one of my shop made blocks and its always possible I screwed something up.

Remove the two plugs on the top of the block and use a drill bit to verify those holes are aligned with the ports in the tractor side. Also check that the end ports are aligned with the top ones.

Dan

 

[Russell King]

Please clarify that when you say right and left you mean in relation to the picture not in relation to the tractor?

Yes left and right in picture. The picture is taken looking from the front towards the rear end of the tractor. Sorry I didn’t clearly state what I meant to convey.

 

[Russell King]

Then put the OEM outlet cover bsck on and see if the heating problem goes away before tearing the pump spart.

You might also check the fit on the replacement diverter block. You hxve one of my shop made blocks and its always possible I screwed something up.

Remove the two plugs on the top of the block and use a drill bit to verify those holes are aligned with the ports in the tractor side. Also check that the end ports are aligned with the top ones.

Dan

I have looked at the splitter block in the past pretty closely but will look at it again. But I am pretty sure it is correct and that it aligns with the original holes on the tractor.

One more thing I noticed is the size difference in the original hard tube on the tractor (approximately 1/2 inch OD?) and the size of the tube on the 90 degree end of the hose that is shown above (approximately 1/4 inch OD). I’ll have to measure them to be sure they are significantly different. I just noticed that by eyeballing them but didn’t measure them.

Thank you for the suggestions and assistance.

 

[TheOldHokie]

I have looked at the splitter block in the past pretty closely but will look at it again. But I am pretty sure it is correct and that it aligns with the original holes on the tractor.

One more thing I noticed is the size difference in the original hard tube on the tractor (approximately 1/2 inch OD?) and the size of the tube on the 90 degree end of the hose that is shown above (approximately 1/4 inch OD). I’ll have to measure them to be sure they are significantly different. I just noticed that by eyeballing them but didn’t measure them.

Thank you for the suggestions and assistance.

I assumed you used 3/8" hoses and JIC-8 hose ends. That is mominally 3/8" ID hose and what Kubota uses on their OEM hoses. The metal hose ends will be roughly 3/8 OD but should not cause a problem.

I would favor using the top ports on the block over the end ports.. That eliminates that abrupt 90 degree internal turn with sharp edges. The MJX90 hose ends have a much smoother and longer radius.

Dan

 

[Russell King]

I assumed you used 3/8" hoses and JIC-8 hose ends. That is mominally 3/8" ID hose and what Kubota uses on their OEM hoses. The metal hose ends will be roughly 3/8 OD but should not cause a problem.

Dan

3/8 hose but used JIC -6 swivel ends on the hoses and adapter fittings SAE -8 to JIC -6

I told the vendor the flow rate of the pump and took their recommendation for the ends.

And I assume the pump is the original flow rate and has not been updated. But have no idea on the pump - it was just on the tractor when I bought it.

 

[TheOldHokie]

3/8 hose but used JIC -6 swivel ends on the hoses and adapter fittings SAE -8 to JIC -6

I told the vendor the flow rate of the pump and took their recommendation for the ends.

And I assume the pump is the original flow rate and has not been updated. But have no idea on the pump - it was just on the tractor when I bought it.

MJX90-06-06 hose end will be 3/8" tube with.a JIC6 nut and a 3/8" barb

MJX90-08-06 hose end will be 1/2" tube with a JIV8 nut and a 3/8" barb.

Not much difference there and we are talking a scant 4 GPM flow. Probably splitting hairs.

Dan

 

[North Idaho Wolfman]

I agree with TheOldHokie, but I wouldn't use the top holes I would use the face ports, they would be the free flow.

 

[TheOldHokie]

I agree with TheOldHokie, but I wouldn't use the top holes I would use the face ports, they would be the free flow.

Thats what I meant by top. The others are end and side ports in my lexicon

Dan

.

 

[Russell King]

I am currently using the end ports and the an additional 90 degree fitting on the pump side of the block, the power beyond side has a straight fitting and then the 90 degree on the hose end.

I did it that way to keep the hoses out of the way of my feet getting onto the tractor. I may have to reconsider that if the original block runs considerably cooler. I may also replace the two hoses with larger size hose and fittings just to eliminate the friction there.

I should be able to do some more troubleshooting on Saturday. I just never expected to have any type of trouble like this by adding a rear valve so I am somewhat frustrated and would rather be working on something else than troubleshooting! But I will definitely stick with it until I get it resolved.

Thank you both for your help, I really appreciate it.

 

[Russell King]

MJX90-06-06 hose end will be 3/8" tube with.a JIC6 nut and a 3/8" barb

MJX90-08-06 hose end will be 1/2" tube with a JIV8 nut and a 3/8" barb.

Not much difference there and we are talking a scant 4 GPM flow. Probably splitting hairs.

Dan

Is that the outer diameter or the inner diameter of the tube? While it is probably not important I just am too curious not to know and can’t find the information on the internet yet.

 

[TheOldHokie]

Is that the outer diameter or the inner diameter of the tube? While it is probably not important I just am too curious not to know and can’t find the information on the internet yet.

Hose dash size indicates inner diameter of the hose.

Tube dash size indicates outer diameter of the tubr. The inner diameter varies with the wall thickness (pressure rating) of the tube.

As a rule of thumb for 3000 PSI tractor hydraulics a 3/8" hose (-06) is roughly equivalent to a 1/2" tube (-08).

A 3/8" hose is more than adequate on your 4 GPM tractor. You will gain nothing switching to bigger and bulkier hoses. FIrst thing to eliminate is that hard 180 degree turn created by using the end ports. Just move the fittings to the top ports and see.if it makes any difference.

My gut says it wont and your problem lies elsewhere. It would be nice to have a pump outlet pressure reading to see exactly how much back pressure the remotes are adding but the OEM plumbing does not make that easy. One thing for sure - your problem is not typical.

Dan