Single Acting Cylinder on Double Action Valve

[dieselscout80]

Question my Woods C114 has a cylinder that only has one hose aka single acting (power up and gravity down).

I just got a New Holland factory valve for my TC45DA that did not have a valve from the factory and is spring centered and can power in and out aka double acting.

If I plug a single hydraulic line into that valve, will it allow a single acting cylinder to lower via gravity when the valve control handle in is the spring centered position?

 

[ptsg]

So you will move the lever one way to lift. In center position, the cylinder just holds position.

To lower, you would move the lever to the opposite way. However, this will dead head the pump and force the fluid through the relief at max pressure, which can cause heat and damage over time. Ideally you would connect the unused port to the tank.

 

[LouNY]

It is really unfortunate that so few valves added to tractors do not have a float position, as that is the best method of "lowering" removing the pressure from a single action cylinder. It also works quite well for allowing hydraulic motors to coast to a stop.
Using your valve will allow the single acting cylinder to retract while held in the opposite way which extends it, it does dead head your pump and makes the pressure relief valve work more than it's nice to. When I use my tractor which does not have a float valve on an implement with a single acting cylinder I will dead head the system till the implement is lowered then every once in a while I'll give it another couple of seconds to try and lower again.
If you have removed your loader and will not be using it while mowing you could run hoses back to the implement from the loader lift circuit which likely has a valve with float.

 

[MtnViewRanch]

For your existing circumstances, the safest way to lower the implement is to turn the tractor off.
Then use the lever to lower the implement down to the desired position.

 

[dieselscout80]

Sounds like I need to just get a double acting cylinder. I would want to raise and lower the mower as I cut pastures when I get to tall spots that start to pull down the tractor's rpms and then lower it again while still cutting at speed (say 3.5 mph).