My splitter seems to have an air pocket in the cylinder. It hesitates while splitting and kind of jumps forward. Is there any way for air to be getting into the system but not fluid to be leaking out? The fluid is also gray in color. I changed it < a year ago. I attached a pic from the day of its purchase, just to give an idea of the plumbing. I have replaced most of the hoses, the engine, rebuilt the cylinder etc..... Thanks for any help.