Hose connecting swing cylinders???

[paulchace]

For the 713 backhoe at the back of the cylinder tubes is a whole where previously some sort of vent was installed. I have just such a machine and I vaguely remember reading where there is a kit available to join each vent hole with a hose.
Seems practical, unfortunately my machine had no vent on the passenger side swing cylinder tube and had a plug on the driver's side cylinder tube. I dropped the plug today and didn't get a look at it to see if it was actually a vent but my question is does anybody know more about this??
Thank you!

 

[JoeM(GA)]

If I remember correctly, those are one way cylinders, you must have a vent or a hose joining them together to keep from having a vacuum. Many people
took the hoses off when the packing began to leak and filled up behind the piston