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

 

[jsjsteven]

I'd say you need a vent for sure. McMaster-Carr

 

[ttouring]

No one has mentioned the possibility of being a mechanical issue like something outside the cylinder links pivots etc. I believe I'd remove the cylinder and move it in and out to check it.
If still stops early then it's in the cylinder if not.

 

[gsldirtman]

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!

The plugs are solid so when the wings are up there is air pressure to help wings come down. When they won’t go all the way up just pull the plugs and raise the wings, oil that has seeped past the internal seal will come out. Lower the wings and reinstall plugs. I do this yearly and get a few ounces of oil out of each wing, which is normal. It’s actually a good design.
Good luck!

 

[sequoyah101]

Everybody else has had a piece of this so why not me?

Wear and leakage. In operation the spool is in float. The wing goes up and down and the piston wears in the cylinder in just one region all the time. It gets worn at that spot and leaks into the cap end when the piston moves by the worn spot under pressure, there is little pressure on the spot in operation as the spool is open to the tank in float.

Drain the leakage and you may need a new cylinder or just live with the leakage and drain it. If the bore is NOT bad just a rebuild may fix it.

There is also a safety transport strap on each side or small hooks on each wing. I chain mine up when not in use and relieve pressure on the cylinders putting the spool in float when the wings are chained up then close the valve. They will leak down of course but I store the wings up and can't let them lower.

I have not yet had the problem on my Rhino but expect it any time since it has 15 or 16 seasons on it. All barn kept but time takes its toll.

The paint on these machines is lousy. Mine look like lepers and have only been outside to work.

 

[rockinbbar]

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.

Yeah, I had a Woods BW12 that would do that, as well as have the wing hinge joints seize up due to not being able to grease them.

In this case everything is good on this cutter. Drive shafts are straight and well greased to retract, and the wing hinges are loose fitted and have always worked well.

To remedy this, I bought a couple of vent plugs to install on each wing cylinder to relieve the off side cylinder pressure. Being 10 years old, and seeing quite a bit of use, I imagine the cylinder seals need redone in a couple years, but the new vent plugs should get me down to that point in time. When they start weeping fluid excessively, I'll rebuild the cylinders.

 

[9501tts]

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!

 

[9501tts]

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!

 

[9501tts]

I also own a Woods 15ft batwing mower. I noticed the same thing,a solid plug in the other port. The wing cylinders are plumbed for single action and only retract. When you reverse the hyd oil flow the cylinder extends & the wing comes down only by the force of gravity. If you are on a side slope & the wing is tipping inwards the wing will not come down until you get on level ground and gravity takes over. When I saw the solid plug in the other cyl port I assumed the factory had assembled the cyl that way to prevent any contamination as new cylinder are shipped with solid plugs in both ports. Replaced plug with a vent plug. Leaving the solid plug in would have put that end of cyl under a vacuum when extended. The mower assembly instructions should have mentioned this.

 

[sequoyah101]

I have to offer a correction / retraction about travel of the wing cylinders as the wings flex up and down. Many, perhaps most batwing mowers have some sort of mechanical flexure mount for the rod end of the single acting lift cylinder (double acting cylinders can be had but I still don't see the benefit)

The Rhino FR-15 I have has mechanical flexure mounts like I've shown in the picture attached. They are pretty robust. Newer models just use slots I have never observed them to move but I'm sure they probably do as I get in the ditches and on pond banks and such.

 

[TishaDele]

I had a similar issue with the hydraulic cylinder on my mower last year where it wouldn’t fully retract, and it was because of internal leakage. Even though I didn’t see any external leaks, the seals inside were allowing fluid past, which caused it to stop just short of the full retraction. I ended up rebuilding the cylinder, and it worked like a charm again. If you're not seeing leaks and it's only a slight issue, a rebuild might be the way to go. I’ve found that places like Northern Hydraulics have solid hydraulic cylinder components and gear pumps if you need replacements.