Not really forestry, more like arborist but this will do. This lift belongs to one of my customers. He bought it for me to work on his property. I have been using it for about 10 years. The last few days I have been topping dead oaks.
Once the boom and dipper arm are up, the upper portion of the lift can rotate on the base.
There is a hydraulic motor that provides power for this rotation.
I recently noticed that there is a hydraulic leak from the cap of this motor. I contacted Teupen USA but they will not provide me with any information. I want to replace the gasket between the cap and the motor body but I have never been into something like this before. I am thinking that the cap may be just that, with a bearing in the motor body. The cap could also house the bearing. I doubt that there will be any springs or such to pop out when I remove the cap but I don’t know. Any advice would be appreciated.
That is a bearing cap. You should be able to remove the bolts and lift it straight off. There should be a tapered bearing race in the cap itself but it will stay in the housing. It should be pretty simple.
Those are slick units for tree trimming. Hired a local company that had one similar but yellow, can't remember the name that took down a 3' diameter pine in my back yard that was hit by lightning. Set up to tree down time was pretty damn impressive and no climbing.