Non-functioning hydraulics

[Dashman]

My fitting arrived today, and I affixed it to the end of the hose from the outlet of the hydraulic block (inlet of the loader valve). When I started the tractor there was no pressure, but a lot of fluid came out of the inlet port of the loader valve. I realized I need to place the hydraulic block spool in the vertical position. Then a lot less fluid came out of the inlet port of the loader valve. I'm at a loss. Something's fishy, and I'm less sure that's it's the pump.

Starting at the hydraulic block, this is what I have:
1/C inlet to remote valve power beyond
3/B outlet to loader inlet
4/D tank to loader outlet

At the loader valve:
inlet to outlet of block
outlet to tank with tee 2
power beyond to remote valve inlet

At the remote valve:
Inlet to loader power beyond
Outlet to tank with tee 3 (end 1 into hydraulic block port fitting)
power beyond to hydraulic block inlet port

It's like flow is in reverse. What do you all think now?

 

[Russell King]

I am not sure what you really mean but the hoses and valves seem incorrectly connected.

1=C should be the hose that is coming from the rear remote power beyond port
3=B should be the hose that goes to the loader valve power in port
4=D should be the tank return for both the rear valve and the loader valve. There should be two separate hoses (one from each valve) that could be TEEd together and then connected to the tractor block to return to the sump.

It should be a loop from tractor pump to block to valve power in through valve to power beyond sleeve port to valve power in through valve to power beyond sleeve port then back into tractor block to power the three point hitch and then dump to the sump. Then the two tank lines need to go from the valves to the tractor sump.

Confirm you don’t have a second block on the rear of the tractor

 

[Dashman]

I'm not seeing what you believe is incorrect. It seems that you've stated what I have in just a different manner than what I did. If I followed your hose connections perfectly, there wouldn't be a hose swap. Please be more specific as to where my mistake is. I believe that you are correct, some hose is incorrect. I will add that my hose connecting FEL power beyond to remote inlet, is unique and shorter than the other two hoses at the FEL valve. It's also unmistakable that the FEL valve outlet hose is connected to the tank tee at the hydraulic block. Then the FEL valve inlet hose is connected to the outlet of the hydraulic block. The outlet port of the hydraulic block is the pressure port, correct?

I believe I do have a loop. Pump to hydraulic block outlet to loader inlet through valve from loader power beyond to remote inlet through valve from remote power beyond to hydraulic block inlet. The two outlets are connected to a tee and into the tank.

The way the pressure hoses are routed the FEL valve is pressurized first, then the remote valve, then the 3PH when the spool slot is vertical. Otherwise, the 3PH is pressurized when the spool slot is horizontal, as when the FEL is removed. Recall, I already tried rotating the slot horizontal, and with high RPM the 3PH would raise very slowly.

No second block at rear of tractor. A steel tube connects the hydraulic block to the 3PH. There is no outlet to the hydraulic block it must just spill into the tank.

Did I need to cap the loader inlet port while I connected the pressure gauge to the end of "hose 6"?

 

[Russell King]

Ok what you are saying sounds correct but turning that block valve to a different position to stop flow out of the FEL valve inlet seems wrong and indicates a hose is installed incorrectly to me.

I don’t know what hose #6 is.

Test the pressure as suggested by @TheOldHokie in a previous post. (I am not sure what you are doing when you are pressure testing.)

Take some pictures of your hoses and connection points, clearly marking the hose ends with color or letters or numbers.

Try to remove all hoses from the block as if there is nothing extra on the tractor. Then set the block valve to the correct position (horizontal as I understand it). Then see if the three point hitch operates correctly.

Or take the rear remote out of the equation and just have the FEL valve hooked to the tractor block. Turn the block valve to the correct position (vertical as I understand it) then the FEL and 3PH should work.

Then you can add the rear remote back in if everything is working.

And be sure you understand that a tank return port is different that a power beyond sleeve port but both are outlets of the same valve. And that only tank return lines can be TEEd together to get to the sump port.

I am still stumped because you say it is connected correctly but doesn’t work properly. If it is not working properly then it is not connected properly. I have seen @TheOldHokie active lately so perhaps he will make some suggestions for you to try.

 

[Dashman]

In my photos:
Red = outlet, pressure. 3/B, Hose 6, FEL inlet
Green = inlet, Power Beyond. 1/C, Hose 5, FEL PB stock, Remote PB current
Md. Blue = FEL Tank. 4/D, Hose 7, FEL outlet stock
Lt. Blue = Remote Tank. 4/D, Remote outlet current

Numbers, letters, and hoses are from the LB552 Operator's Manual.

When I hooked up the pressure gauge as shown, and started the tractor, fluid flow was out of the FEL inlet port. That's where I had removed the hose from to install the pressure gauge. ...of course there was no reading on the pressure gauge.

 

[TheOldHokie]

Keep it simple. Measure pressure at port B on the outlet block. If it is not 2500 PSI the selector is in the wrong position or the pump is not working.

Dan

 

[Dashman]

I used my air compressor with a rubber tip to put about 35 psi on the outlet hose from the hydraulic block. If it was somehow flowing in reverse before, I wanted to try to switch that. I also hooked up one of my old hoses to the FEL valve inlet port to try to better capture any oil that would come out of that port again. I held the outlet hose into a bucket, and started the tractor. It made a pretty strong stream.

I refilled hydraulic oil to a level in the sight glass, and I installed the pressure gauge as before. The tractor wouldn't start because the oil was "deadheading" at the gauge. It would temporarily max out the gauge to over 3,000 psi. It was two attempts to start for 3 seconds each time just cranking, no engine start.

I thought, ok this is something new, and I connected the outlet hose back to the FEL valve inlet. Nada. I switched the "control screw" back to horizontal, and with 1,800 RPM the 3PH would rise slowly again. With the "control screw" in the vertical position, nothing would work. I hold the FEL control down to lift the bucket with 1,800 RPMs, and nothing.

Could the water contaminated oil have heated up enough to ruin the regulator spring in the hydraulic block? Also, what about the load lock springs in the FEL control valve? I had no washer in the regulator, I tried (1) washer with no change, and (2) washers with no change. I'm still not convinced that the pump is bad, but I'm not figured out what else it could be.

 

[TheOldHokie]

I used my air compressor with a rubber tip to put about 35 psi on the outlet hose from the hydraulic block. If it was somehow flowing in reverse before, I wanted to try to switch that. I also hooked up one of my old hoses to the FEL valve inlet port to try to better capture any oil that would come out of that port again. I held the outlet hose into a bucket, and started the tractor. It made a pretty strong stream.

I refilled hydraulic oil to a level in the sight glass, and I installed the pressure gauge as before. The tractor wouldn't start because the oil was "deadheading" at the gauge. It would temporarily max out the gauge to over 3,000 psi. It was two attempts to start for 3 seconds each time just cranking, no engine start.

I thought, ok this is something new, and I connected the outlet hose back to the FEL valve inlet. Nada. I switched the "control screw" back to horizontal, and with 1,800 RPM the 3PH would rise slowly again. With the "control screw" in the vertical position, nothing would work. I hold the FEL control down to lift the bucket with 1,800 RPMs, and nothing.

Could the water contaminated oil have heated up enough to ruin the regulator spring in the hydraulic block? Also, what about the load lock springs in the FEL control valve? I had no washer in the regulator, I tried (1) washer with no change, and (2) washers with no change. I'm still not convinced that the pump is bad, but I'm not figured out what else it could be.

Slow down and go step by step.

You get reverse flow through loader valve when the selector is in the wrong position

3000 PSI at the outlet indicates the selector is in the correct position and the main PRV is not opening at the desired pressure.

Reconnect the pump supply to the loader valve and connect the gauge to the power beyond port on the loader valve. That adds the loader PRV to the circuit. Check pressure with the gauge connected to the PB port.

Dan

 

[North Idaho Wolfman]

I used my air compressor with a rubber tip to put about 35 psi on the outlet hose from the hydraulic block. If it was somehow flowing in reverse before, I wanted to try to switch that. I also hooked up one of my old hoses to the FEL valve inlet port to try to better capture any oil that would come out of that port again. I held the outlet hose into a bucket, and started the tractor. It made a pretty strong stream.

I refilled hydraulic oil to a level in the sight glass, and I installed the pressure gauge as before. The tractor wouldn't start because the oil was "deadheading" at the gauge. It would temporarily max out the gauge to over 3,000 psi. It was two attempts to start for 3 seconds each time just cranking, no engine start.

I thought, ok this is something new, and I connected the outlet hose back to the FEL valve inlet. Nada. I switched the "control screw" back to horizontal, and with 1,800 RPM the 3PH would rise slowly again. With the "control screw" in the vertical position, nothing would work. I hold the FEL control down to lift the bucket with 1,800 RPMs, and nothing.

Could the water contaminated oil have heated up enough to ruin the regulator spring in the hydraulic block? Also, what about the load lock springs in the FEL control valve? I had no washer in the regulator, I tried (1) washer with no change, and (2) washers with no change. I'm still not convinced that the pump is bad, but I'm not figured out what else it could be.

You have a relief valve issue in the hydraulic block!

You should not be able to deadhead the pump no matter what you do!
The relief valve is not relieving pressure, then it not closing allowing it to build pressure.
So nothing is working right.
Pull the Hydraulic block out and get it on a bench to work on.

 

[TheOldHokie]

You have a relief valve issue in the hydraulic block!

You should not be able to deadhead the pump no matter what you do!
The relief valve is not relieving pressure, then it not closing allowing it to build pressure.
So nothing is working right.
Pull the Hydraulic block out and get it on a bench to work on.

View attachment 149351

The relief opens to limit pressure. The relief valve is not causing a loss of hydraulic function.

Dan

 

[Dashman]

This particular HUSCO 9210 Loader control valve (LB552) does not have a pressure relief valve. It has a plug in the port where a PRV would be for a different model of loader.

Dan, you're correct. With the "control screw" horizontal there seems to be back flow through the FEL valve. Pressure was 250 psi in the horizontal position, and in no time a 5 gallon bucket filled to 4 gallons. Then I switched the control screw to vertical, started the tractor, and it shot up to over 3,000 psi, and I shut it down.

I've had the hydraulic block PRV removed and inspected. That's how I know it didn't have a washer or any shims. I even measured the length of the spring to be 1.71 inches, but I don't know what length it's supposed to be. The seat and poppet looked fine, and I didn't see any debris that would impede its operation. Is the plug supposed to be threaded on snug tight? ...or is it supposed to have some adjustment by not being tightened all the way?

Wolfman, you want me to remove the hydraulic block, disassemble it, clean it, and fully inspect it? Ahhh, I get it, you're thinking some debris might be interfering with the inlet to the PRV. Ok, that's what I'll do tomorrow.

Thank you guys!

 

[TheOldHokie]

This particular HUSCO 9210 Loader control valve (LB552) does not have a pressure relief valve. It has a plug in the port where a PRV would be for a different model of loader.

Dan, you're correct. With the "control screw" horizontal there seems to be back flow through the FEL valve. Pressure was 250 psi in the horizontal position, and in no time a 5 gallon bucket filled to 4 gallons. Then I switched the control screw to vertical, started the tractor, and it shot up to over 3,000 psi, and I shut it down.

I've had the hydraulic block PRV removed and inspected. That's how I know it didn't have a washer or any shims. I even measured the length of the spring to be 1.71 inches, but I don't know what length it's supposed to be. The seat and poppet looked fine, and I didn't see any debris that would impede its operation. Is the plug supposed to be threaded on snug tight? ...or is it supposed to have some adjustment by not being tightened all the way?

Wolfman, you want me to remove the hydraulic block, disassemble it, clean it, and fully inspect it? Ahhh, I get it, you're thinking some debris might be interfering with the inlet to the PRV. Ok, that's what I'll do tomorrow.

Thank you guys!

The problem IS NOT the relief valve. If youvwant to wasre more time have at it.

The PRV may be stuck or set wrong but if you have 3000 PSI or more at the loader valve the loader and 3pt should work.

Dan

 

[North Idaho Wolfman]

The relief opens to limit pressure. The relief valve is not causing a loss of hydraulic function.

Dan

If it's sticking open it most certainly can cause a loss of system pressure.
The 3000PSI and deadheading enough to not allow it to start would indicate a stuck PRV.

So he's getting both, it being stuck open, and it being stuck closed, randomly, like a bad poppet or spring or something stuck in the block?

 

[TheOldHokie]

If it's sticking open it most certainly can cause a loss of systeem pressure.
The 3000PSI and deadheading enough to not allow it to start would indicate a stuck PRV.

So he's getting both it being stuck open and it being stuck closed, randomly, like a bad poppet or spring?

Stuck or not, with 3000 PSI the loader should work.

Dan

 

[Russell King]

@TheOldHokie or @North Idaho Wolfman
Can you explain how fluid would come out of the FEL power in port if the hose from the tractor block port B (power to implement) is disconnected from anything except a guage?

(That is what I understand @Dashman is stating has happened, but I can’t fathom how it could happen)

 

[North Idaho Wolfman]

@TheOldHokie or @North Idaho Wolfman
Can you explain how fluid would come out of the FEL power in port if the hose from the tractor block port B (power to implement) is disconnected from anything except a guage?

(That is what I understand @Dashman is stating has happened, but I can’t fathom how it could happen)

My first thought would be from the cylinders bleeding down, could even be the three point cylinder.

 

[TheOldHokie]

@TheOldHokie or @North Idaho Wolfman
Can you explain how fluid would come out of the FEL power in port if the hose from the tractor block port B (power to implement) is disconnected from anything except a guage?

(That is what I understand @Dashman is stating has happened, but I can’t fathom how it could happen)8

With the selector in the wrong position and the inlet open the PB port on the valve is still teed into the pump line going to the 3pt. That creates a reverse flow loop through the open center in the valve.

Flow is pump to B which is blocked by the gauge. Then continues through diverter to C where it divides. Some flow cntinues to 3pt but some is pumped out C into PB port, through the open center, and then out the linlet port. Draw it up.

Dan

 

[North Idaho Wolfman]

With the selector in the wrong position and the inlet open the PB port on the valve is still teed into the pump line going to the 3pt. That creates a reverse flow loop through the open center in the valve.

Flow is pump to B which is blocked by the gauge. Then continues through diverter to C where it divides. Some flow cntinues to 3pt but some is pumped out C into PB port, through the open center, and then out the linlet port. Draw it up.

Dan

This is only possible if the diverter selector is in the is in the non diverted position.
My understanding and the pictures show that diverter is in the diverted position when this happened.
Or it's very possible that I've missed some detail along the way????

 

[TheOldHokie]

Ye

This is only possible if the diverter selector is in the is in the non diverted position.
My understanding and the pictures show that diverter is in the diverted position when this happened.
Or it's very possible that I've missed some detail along the way????

Yes, thats what I said early on. It happens when the diverter is in the wrong position. The testing and descriptions have been all over the map but he clearly tried it both ways. I am trying to bring some order and clarity to the testing.

With the diverter in the correct position he gets no reverse flow and 3000 PSI at the B port. Why doesnt the loader work in that position? My WAG is PB is blocked somewhere downstream. A little more controlled testing at the loader valve will tell the story.

Dan

 

[Dashman]

Dan, as I'm following you all's advice, I'm getting you want me to get pressure readings from the FEL valve PB and remote valve PB. I'll get those pressures later this morning.

Thanks for the explanation about how the reverse flow can be happening. Yes, it's only with the "control screw/diverter/spool" in the horizontal position. I found that out yesterday when I collected 4 gallons from the FEL valve inlet port. I understand that for loader or remote operation the "control screw" needs to be in the vertical position. I only switched to horizontal to isolate the 3PH, and diagnose why it wasn't working. I have verified the hose configuration multiple times because I understand I could have made a simple mistake. I wouldn't ask for help on a forum, if I hadn't already done my diligence.

I've been using a cloth to filter those 4 gallons back into a container to bring the tank level back into the sight glass for testing today.

Yes, the big question is: Why is there flow with pressure, but the loader and 3PH don't move?

My issues started with water contaminated fluid, a bad FEL valve float detent, and oil leakage from the quick disconnects. ...but it was working. I already had parts and seals for the HUSCO valve, so I removed it, cleaned it, and disassembled it. When I got to the bare valve block, I sprayed degreaser into the bores, rotated it, dunked it into hot soapy water, then I sprayed brake cleaner into the bores. The brake cleaner came off the block clean, so I called it good. Honestly, I didn't inspect the bores after the brake cleaner. The spools didn't show any scratches, chips, and wear marks. I reassembled with light swipes of vaseline, and everything went back together normally.

I'm going to finish filtering the oil for reuse, and get those PB pressures. Thanks!