Backwards spool valve??

[JLeus]

I am putting a 3 spool valve on a MF 255 for loader control to accommodate a grapple. It has a joy stick (2 spools) currently and I am gathering parts for the change. I am down to getting correct bushings/plumbing parts, I have bought the new valve.

So I am studying the hose layout that is there and I swear the pressure line feeding the current valve is on the return side of the valve and the return line or tank line is on the pressure side of the valve. Looking at just the supply port and return port, I am believing the supply/pressure port is closest to the pressure relief valve. And that hose that is in the port closest to the relief valve goes to the side cover not the aux pump outlet on my machine.

I have looked at this thing 20 times tracing hoses. The old joystick doesn't have marks at the ports that I can see.

Will a spool valve work if the pressure hose is on the return/tank port on the valve??

The spool valves I have looked at, the relief valve is close to the pressure port.....is this a hard rule or indication to go by?? Was there valves that the relief was down stream of the spools?

As always, thanks for your help.

Jim

 

[used red MN]

Does the valve have a brand on it or a number? Often by that you can get the flow diagram. Although your theory about the relief valve being close to the inlet may be good, it may also be close to the return port so the relieved oil can flow into the return cavity. A picture of the valve would also be helpful.

 

[Mike(NEOhio)]

Usually the ports are numbered. No. 1 is the input port and 2 is the return for 1.

 

[JLeus]

Just in case someone lands on this one looking for answers.On my MF 255 with auxillary hydraulic pump the pressure line comes out of the tractor on the round plate at my left heal and the return line goes to the filter under the left trumpet.

I had convinced myself otherwise.

Thanks

Jim