One Way Cylinder Plumbing For a Remote Connection

KPbucker · Nov 21, 2010

Hi everyone, I'm new to the forum so I hope I'm not asking a repeat question. I had a junk forklift sitting around and I decided to steal the mast off of it to make a 3-point hitch forklift that runs off of the remote of a small tractor (Ford 1620 or McCormick GX50). The welding was easy enough and it would be useful for unloading pallets from semi trailers. The forklift was an older style that had a single one-way cylinder responsible for raising and lowering. As it is a one-way cylinder (with only one hose) I first tried to attach it to the remote using only one connect. That would only move the cylinder one way. I then put a "tee" in the line so that the one line would plug into both connections for the remote, and I still had the same issue. Does anyone have any suggestion on how to get this plumbed in correctly? This issue has been bugging me for quite a while and I would really like to get to the bottom of it.

J_J · Nov 22, 2010

When connected a single action cyl to a DA valve, connect the cyl hose to the A port, and plug the B port.

KPbucker · Nov 22, 2010

Thanks for the advice. I will definitely try that. In my first attempt the "B" port remained closed since it didn't have a hose attached to it. Can you tell me why adding a plugged hose will give a different result? What is it about the plumbing that makes the difference?

J_J · Nov 22, 2010

The fluid will follow the path of least resistance. If valves are in parallel, and you operate one lever. the fluid will just flow through the other valve and go to tank.

So when you activated one lever on a valve, you put a block on that valve, and the fluid was forced to flow through the other valve.

The reason for the plugged B port, is so you don't accidentally cause fluid to flow out that port. Since there is no return for the rod side of the cyl, why use the B port.

A single cyl retraction is caused by the weight of the attachment , or a spring in the cyl.

KPbucker · Nov 22, 2010

That makes sense. Thanks for the help, this issue has been bugging me for quite a while. I went into the local New Holland dealer and even they didn't have an answer for me. I appreciate the help, and if anyone else has anything to add I'd like to hear it. Thanks!

kennyd · Nov 22, 2010

KPbucker said:
Hi everyone, I'm new to the forum so I hope I'm not asking a repeat question. I had a junk forklift sitting around and I decided to steal the mast off of it to make a 3-point hitch forklift that runs off of the remote of a small tractor (Ford 1620 or McCormick GX50). The welding was easy enough and it would be useful for unloading pallets from semi trailers. The forklift was an older style that had a single one-way cylinder responsible for raising and lowering. As it is a one-way cylinder (with only one hose) I first tried to attach it to the remote using only one connect. That would only move the cylinder one way. I then put a "tee" in the line so that the one line would plug into both connections for the remote, and I still had the same issue. Does anyone have any suggestion on how to get this plumbed in correctly? This issue has been bugging me for quite a while and I would really like to get to the bottom of it.

Welcome to TBN

This is done all the time, no reason it shouldn't work on your machine. The port that the cylinder is plugged into will be open to the tank when the valve is operated the "other" way allowing the cylinder to rectract if there is enough weight pushing on the cylinder. While this is happening, the tractor will sound a little labored since the hydraulic system is "in relief" but it won't cause any problems. To keep the system out of relief you can plumb a hose from the unused port on the valve to the tank.

Take that Tee out