Hydraulic Cylinder Question

[Jkott]

Could be possible that the nut has started backing off the piston shaft. I had one ram on my excavator do that.

Rebuilding it will definitely tell you what’s wrong.

 

[Mike1955]

It could also be that it has formed rust or accumulated dirt in the bore on the retracted side.
I have a one way cylinder on a Rgino GR84 with vent plug. The oil seeps by the piston slightly and blows out the vent hole.

So does mine

 

[LD1]

Im in the same camp that thinks you have some fluid bypassing.

I just helped a neighbor on a little 10-ton single axle dump with a scissor hoist. Rod side port had no vent. But would only dump about half way.

He called me for help to disassemble the scissor hoist thinking he had a seized pin or something. I took that plug out and had him try again. It went all the way up and purged the oil out of the "blind" side.

Not really practical for a tractor......but rather than rebuild the cylinder on an old farm truck, we just ran a 1/4" hose from that port back to the reservoir so any future leakage would be reclaimed and not cause any issues again

 

[4570Man]

Im in the same camp that thinks you have some fluid bypassing.

I just helped a neighbor on a little 10-ton single axle dump with a scissor hoist. Rod side port had no vent. But would only dump about half way.

He called me for help to disassemble the scissor hoist thinking he had a seized pin or something. I took that plug out and had him try again. It went all the way up and purged the oil out of the "blind" side.

Not really practical for a tractor......but rather than rebuild the cylinder on an old farm truck, we just ran a 1/4" hose from that port back to the reservoir so any future leakage would be reclaimed and not cause any issues again

I think the OP would be fine to vent the cylinder to allow the oil to squirt out as long as you did it in a fashion that didn’t allow water to enter. The seals are apparently barley leaking otherwise the barrel would be more than an inch full. If the leak became bad enough that the oil loss became a problem then he would have to reseal it.

 

[LouNY]

Solid??? How does the cylinder vent then?

Using a solid plug the air filled side of the cylinder acts as a cushion so it doesn't slam. There is usually enough air leakage past the rod seals to vent what it has to. If it gets fluid on the plugged side it can gum up and limit travel.

 

[rockinbbar]

I think the OP would be fine to vent the cylinder to allow the oil to squirt out as long as you did it in a fashion that didn’t allow water to enter. The seals are apparently barley leaking otherwise the barrel would be more than an inch full. If the leak became bad enough that the oil loss became a problem then he would have to reseal it.

Got some vent nuts for the cylinders. Might as well do both.
As long as they don't squirt out too much fluid, I can wait awhile to re-seal them.

 

[rockinbbar]

Using a solid plug the air filled side of the cylinder acts as a cushion so it doesn't slam. There is usually enough air leakage past the rod seals to vent what it has to. If it gets fluid on the plugged side it can gum up and limit travel.

I can agree with that. Even the way it is, those cylinders are powerful, and I'm not heavy handed with the control. I ease them up. I'll probably have to be even easier with control lever after I vent the cylinders.

 

[Gord Baker]

Compare it closely to the other side. With it Well secured as far Up as it will go, carefully remove that plug and see what comes out.

 

[Creekdrifter]

Sorry if I'm repeating what someone said due to not reading all of the conversations. I have a Rhnno 12TS that would bind when raised completely on one side. Turned out to be the PTO shaft for that wing. It was bent just enough to cause a problem when fully retracted.

 

[Bison]

I have a Woods batwing cutter that's about 10 years old.

The cylinder that raises one of the wings has recently started not retracting all the way. Comes close, but stops about an inch shy of where it should be.

That is only a problem because only in the full upright position can I engage my locks on the wings.

Could the cylinder have blow-by fluid on the other side of the seals? It's not been showing any signs of leaking out the other end. It also has a solid plug on the opposite end, as it's just plumbed one way.

Thoughts? Maybe time for a rebuild?

Thanks in advance!

yes oil on the other side of the piston could be the cause. Remove the plug, it should have a breather plug there