selector valve problem

[jurden]

This is my first post on this site. I have been a member for several months and learned MUCH. What i know about hydraulics I've learned here. But, I知 stumped by a hydraulic problem.
I have tried to add another function to the curl circuit on my FEL for a grapple using an electric selector valve. The valve is from Surplus Center and is the valve used in many posts for this purpose. I have it plumbed so that the N.O. circuit operates the curl and closing a momentary S.P. switch operates the valve to switch to the grapple. Problem is: when I curl the bucket or extend the bucket the bucket operates as it should but causes the relief valve to open and the tractor engine to load hard. The bucket rolls forward and back but fluid is also going by the relief valve. The selector valve is rated for 15 GPM. My tractor is 90HP and the hydraulic pump makes 17 GPM per the ownerç—´ manual. So, what do you think? Valve to small for my application? Valve defective?

Let me add that Surplus Center has been VERY cooperative and willing to work with me on this. The tech guy on the phone had me remove the valve, take it apart, and look for a problem. Nothing was found (trash, dirt, casting flash, ect.). When I had the valve apart I did see that the passages were only about 3/16 in diameter. Me? I think the valve is just too small and won稚 handle the volume......al
Link to selector valve:
Burden Sales Surplus Center Item Detail

 

[kennyd]

Welcome to TBN

Does it work OK if you just move the joystick a little bit?
Are you sure both coils have power?
Does the Grapple work OK?

 

[jurden]

"Does it work OK if you just move the joystick a little bit?
Are you sure both coils have power?
Does the Grapple work OK?"

yes the bucket works, but slowly. After 1 or 2 seconds the relief valve "clunks" and the engine is loaded.

both coils work, both plungers in the selector valve will move freely.

grapple has not arrived and and electric selector valve is not powered up.
as i understand it (?), the curl/extend of the bucket should opperate like before i added the selector valve.....thanks, al

 

[mgamber]

I bet we have the same valve. Somewhere there is a thread on here where a user took it apart and found that it is defective (may be why surplus center is selling them). Seems that some of the port holes do not line up correctly and is causing quite a restriction.

 

[tommu56]

jurden
What are the letters on the ports like?

Draw a sketch or take a picture and post it

Is there an mfg # on valve?

It looks like there should be 3 ports on each valve on one side there should be out from system to one port on the other side to cylinder then back to the 2nd valve same position in from cylinder out the other side to tractor return.
unenergized should let one set of ports on each valve function from their respective common ports.

Loop the now unused ports and see what happens.
My bet is you have the lines crossed.

tom

 

[J_J]

jurden ,

Are you applying 12 v to both solenoids at the same time. With no voltage applied, the curl on the bucket is supposed to work as normal. When you apply 12 v to both valves, the circuit switches fluid to the other cylinder, which would be the grapple. .

 

[kennyd]

I bet we have the same valve. Somewhere there is a thread on here where a user took it apart and found that it is defective (may be why surplus center is selling them). Seems that some of the port holes do not line up correctly and is causing quite a restriction.

That was a valve made for Caterpillar, not the one in question here.

 

[kennyd]

jurden
What are the letters on the ports like?

Draw a sketch or take a picture and post it

Is there an mfg # on valve?

It looks like there should be 3 ports on each valve on one side there should be out from system to one port on the other side to cylinder then back to the 2nd valve same position in from cylinder out the other side to tractor return.
unenergized should let one set of ports on each valve function from their respective common ports.

Loop the now unused ports and see what happens.
My bet is you have the lines crossed.

tom

The drawing can be viewed HERE, And the instructions HERE. Hopefully you are correct and it is that simple!

I do not believe the valve's rating of 15GPM vs. the tractor's 17GPM is the issue here. I doubt you have the full17GPM flowing to the work ports of your loader valve. I suspect something very simple...

 

[jurden]

JJ...there is no electrical power to the valve. i had the local hydraulic shop cut the two hose and put new jic 8 ends on the hose. i added the electric selector valve there. so, all hose is the same. the dump/curl input hose are on one side and the 4 outputs are on the other. two original hose (shortened) from selector valve to the cyl. there are no hose on what will be the grapple circuit. the restriction is the selector valve. i checked the hose and cant see any problem with them. i thought the hydraulic shop may have skived some of the hose liner.....al

 

[tommu56]

jurden look at the drrawing at the bottom of the page hydraulic schematic

notice the "T" in the square by the VE, VR ports that means the port is closed in the non powered state. to let fluid flow you need to shift valve (apply 12v power) to get to shift and flow will follow the diagram on the right side of the rectangle.


These are 2 normally closed valves as oppose to a divertor valve you will have to power one or the other to shift functions.

One must be powered at all the time to get that one function to work so you will need a single pole double throw switch to switch functions not just regular push button

This valve is not the normal one normally open circuit and one closed circuit that you would energize the coil to switch function

Ill look for the schametic for a diver tor valve to confuse you more I gotta go to work now

tom