801.4 rotary coupling

[Smarttee]

this appears to be a a hydraulic device located under the slew ring, could anyone explain what it is for and how it works ?
thank you

[ianoz]

Rotary coupling , takes oil from the top of the machine and it goes to the track motors bladee in the bottom end .Can't have hoses going down as they would get twisted off .

[Smarttee]

thank you , Lanoz.

[2414.ginger]

Terry, page 123 in the manual shows you an exploded diagram, which will hopefully give you an inclination as to how it all works.
You should be able to see why when a seal has gone, you will get functions swapping over, (only below the rotary coupling), as in, if you blade down a track will move.