New Remote Valve Not Working--Need some help with troubleshooting.

[npalen]

Just finished installing a cylinder for angle control on my York rake today. Plugged in the QD's and the cylinder would move only a short distance and in only one direction. The newly installed valve Surplus Center - 3 SPOOL 8 GPM PRINCE MB31BBB5C1 DA VALVE appears to not pass fluid when the valve spool is pulled toward the handle but will pass fluid to the cylinder and try to move it when the spool is pushed away from the handle. I opened one of the two tank ports to make sure there wasn't a blockage in the return line. With the port open, pushing the valve handle will let oil out of the port while pulling the handle will NOT allow any oil to drain out of the return port.
I've tried switching hoses at the QD's as well as removing the QD's from the valve, inserting male tips in them and making sure they open, all to no avail. My next idea is to investigate the load check valve which is supposed to keep a cylinder that is under load to keep from "dropping" while the spool is being shifted. It almost acts as if the load check is not releasing when the valve spool is pulled out with the handle. It's very possible that I'm overlooking something simple but could use some ideas.

 

[J_J]

What is the hyd flow path to and from the remote valve.

Did you use the hex screw in the PB port.

The purpose of the load check is to keep the load from shifting, and to prevent the fluid being forced back into the IN port.

 

[npalen]

The path is from the output of the FEL power beyond to the IN port of the new valve, then out the C port (power beyond) and back to the hydraulic block which then feeds the 3PT. The 3PT works fine as does the FEL. Yes, installed the hew screw down inside the PB port.

 

[J_J]

If you have QD's in the circuit, I would check and re-seat them.

 

[J_J]

You have three spools, does it do the same on all three spools?

 

[MtnViewRanch]

I'm only mentioning this because there has been no mention or the 3rd return to tank line. Do you have the return to tank line in place? If not, then I believe that there is no place for the fluid leaving the cylinder to go. :confused3:

 

[J_J]

He said he opened up both return ports and no fluid came out.

It seems to me if you put fluid in one side of the cyl, and there is fluid on the other side, then that fluid has to go somewhere or the relief valve will go off. .

I hope he did not plug both return ports, as that port passes all cyl expended fluid to tank.

If there was a gage in the hyd system, I think he would have seen or maybe not seen any pressures, or correct pressures.

 

[npalen]

I'll try to answer all your questions above, but first will mention that removing the extra plug from the 2nd return or tank port, oil will gush out when the tractor is started. That should not normally be the case unless a valve spool is shifted, right? Yes the other tank port is connected to the reservoir. The PB appears to be working fine for the FEL and 3PT.
I haven't tried the other two spools yet but will do that if all else fails.
Have double checked the seating on the QD's.
The relief valve does bypass when the spool is shifted either direction. The tractor lugs down.
I'm beginning to suspect that the valve was either assembled with the wrong spools or there is some extreme porosity somewhere in the body casting letting pressure go directly to the tank port. It does seem strange that the PB works OK though.

 

[npalen]

Ok guys, I did a couple more tests: Put a gauge on the A and B ports and get a pressure of only 500 PSI when shifting spool each direction. (The B9200 puts out about 2500 PSI)
Switched the QD's over to the second spool and get the same negative results as the cylinder doesn't want to move. (This is a new cylinder and I manually pulled the rod out and pushed back in a couple times before installing) Also tried moving the valve spool with the A and B cylinder ports open and got a gush of fluid out of each port when the spool was shifted to each one. Appears there is volume there but little pressure and I'm guessing that 500 PSI is just a spike.
About to the end of my wits here, hope you guys have some more ideas. It appears that the valve is bypassing constantly to tank but don't understand why the PB, FEL and 3PT would still work.

Edit: Also tried adjusting the relief valve to a higher setting by screwing in a couple turns--made no difference.
Can see the return hose jump a little when first starting the tractor which would be the gush I saw above when starting with one of the tank port plugs out.
Edit II: Removed the PB connection to make sure the hex plug is in place which it is.
Edit III: Valve Info http://www.princehyd.com/portals/0/wolverine/ValveData.pdf

 

[J_J]

No fluid is supposed to flow from the tank/OUT port unless a cyl is moving.

The purpose of the PB hex screw is to separate the tank port from the main gallery flow.

You can use either tank port for the cyl expended fluid.

You did something different when you tapped into the hard return line. Tank flow should be going to tank unimpeded from all valves..

If you somehow blocked tank flow, that will cause back pressure on the input, and give weird problems.

Try running a hose from the remote valve OUT port to the filler cap