Hydraulic control valve

[Gary Sweat]

I apologize in advance if this has been covered before but I didn't see it brought up exactly.
I bought the Bailey joystick control valve 220-910 to put on the FEL I just finished building. The valve did not come with any paper showing the port routing so I figured I could blow air through the valve, move the joystick and see where the air was going. Three of the ports have the raised letters of "P", "T" and "N". I called Bailey and they told me what they mean. P=Pump, T=Tank and N=Power beyond (which is currently plugged).
Here is my question: When I put air to the "P" port and move the joystick I do not get any air out of any port. I reversed the air to the T port, move the joystick and air flows to the correct discharge port so air is moving from (as I understand) the discharge port for that ram to the tank port. Do these type of valves require a certain amount of pressure before the inlet port opens up? I called Bailey and told them this and they promptly sent me another valve in 2 days but it is doing exactly the same thing. I don't want to install this valve and dead lock the pump.

 

[AKKAMAAN]

When I put air to the "P" port and move the joystick I do not get any air out of any port.

Then you most likely have a 'Closed Center valve', the reason you do not get air out through the work port could be that the load check valve is blocking (lightly spring loaded??)

I reversed the air to the T port, move the joystick and air flows to the correct discharge port so air is moving from (as I understand) the discharge port for that ram to the tank port.

You are probably blowing backwards....return into workport

Do these type of valves require a certain amount of pressure before the inlet port opens up?

se above about a spring loaded check valve

I called Bailey and told them this and they promptly sent me another valve in 2 days but it is doing exactly the same thing. I don't want to install this valve and dead lock the pump.

What type of system do you have?? Open or Closed Center??
fixed displacement pump=99.9% open center system (0.1% closed center load sensing with dump valve)

 

[AKKAMAAN]

Most likely, the plug at the power beyond port have to be removed.....to make an Open Center valve

 

[JohninCT]

This link has a link to an instruction sheet for the valve (or one very similar). Bailey web site said that all their valves have load check valves installed. Your air pressure is probably not enough to open the check valve.

Prince Hydraulic Loader Valve - RD522GCGA5A4B6

 

[Gary Sweat]

Thanks guys. It may be that I did not put enough air pressure into the valve since it appears these have a check valve. I put about 40 lbs of pressure on the valve. I will try 135 lbs and see if it opens.
The tractor is a Yanmar 1900 and from what I have read it needs an open center valve. This control valve passes straight through when it is in the center position from "P" to "T" ports. I will be breaking the pressure line from the pump and routing into the "P" port. The tractor pump currently has a pressure line from the pump back to the 3pt and I assume it dumps into the transmission until the 3pt is activated. I thought the valve would work by routing the line out from the "T" port back into the other end of the cut pressure line since the valve passes straight through from "P" to "T" in the center position and when the joystick is moved it opens the discharge port from the ram to the "T" port. The loader kits I have looked at all say to break the pump pressure line and route back out of the other side of the valve to the same line. I don't have a need to power anything at the same time the loader is operating so I didn't think the power beyond would be needed. It has the option to add it. My thinking on the power beyond may be completely wrong on how it works.

 

[JohninCT]

If you look at the drqwing in the link I think it depicts your situation where the 2nd control valve and cylinder represents your 3 point hitch. Pump supply to inlet (P) on loader valve. Outlet (T) should tee into the outlet side of rear hitch and the high pressure supply to the hitch should come from the power beyond port on the loader valve. So, if you cut the high pressure/pump supply to the 3 point hitch. Connect the one end to the loader (P) port and the other to the power beyond port.

http://www.princehyd.com/Portals/0/products/valves/RD5000InstS.pdf

 

[J_J]

The load check on a valve only works to keep the cyl from moving while shifting the levers. There are other valves to maintain a loaded bucket and lift arms.

If you are not using the PB plug, the OC plug will block that port, and allow the supply fluid to flow out the return port, plus the fluid from the cylinders.

Option B is the open center plug.

Which plug do you have in the valve now?

You might need to find out the return port pressure limits. Call Baileys for this.

Maximum tank port pressure on the RD-5000 hyd valve is 500 psi. Do not use the return port to feed hyd pressure to another valve.

 

[Gary Sweat]

Thanks for clearing this up, I think I understand it now. I will need to get the power beyond sleeve for the valve and connect the other side of the pressure line to it so it will feed the 3pt hitch. I guess with this valve, I will also need to route the Tank outlet on the valve to the return line on the tractor with a "T" fitting in order for the cylinders to return oil to the transmission?? The valve has a plug in the power beyond port right now and there is a hole between the tank and power beyond ports connecting them together. I assume that when I put the power beyond sleeve in, it will block the cross connect hole between the tank and power beyond ports?
Sorry for asking so many questions but I don't want to take the chance of shearing the pump shaft if I get it wrong. From what I have read, the pump does not have a relief valve and the output flows through the pto until you move the pto lever and then the pressure is routed to the pto with the excess pressure vented to the transmission.

 

[J_J]

Thanks for clearing this up, I think I understand it now. I will need to get the power beyond sleeve for the valve and connect the other side of the pressure line to it so it will feed the 3pt hitch.

Just to make sure you are understanding me, the pump pressure hose goes to the IN port, and the FEl valve PB port now connects to the 3pt hose.

The Pb sleeve essentially blocks the cylinders expended fluid from the downstream fluid. The expended fluid ,with no pressure, leaves the valve via the return port and goes to tank.

 

[Gary Sweat]

I understand the in and out hookups now and again thanks for the help. The only issue I am trying to figure out now is the tank "T" port. I don't have a tank exactly. The pump pressure line goes directly to the pto and it sits on top of the transmission and I assume it dumps into the transmission via a hole between the two. The suction line comes out of the bottom of the transmission to the pump. There is no actual return line from the pto to the transmission. So, looking at the diagram from the Prince set up, I'm not sure where to run the "T" port to. Can I run it to the suction line or will that cause a vacuum when the control valve is in the neutral position and maybe cause creeping through the valve? When using the PB sleeve, do I still need the "T" port or will the cylinder return oil be routed to the PB port and I just plug the "T" port hole?