I have a 03 YZ250 and changed the fork seals and when filling with oil I'm suppose to pump the rod up and down 10 times to pull oil into the midvalve chamber until the action is smooth. One fork works the other feels like it will not pull oil into the inner chamber. There is no hydraulic action only the feel of the spring. The base valve nut was loose, so I put lock tight on it and tightened it. This changed nothing. Is there an O ring or seal in the midvalve that is allowing air vs. oil to be pulled in?