I have a 1960 centurion 210. I have been having rectractible gear problems. The gear come partially up and stop. Sometimes they drop partially down when I retract flaps after a high density altitude departure. I have sent my hydraulic pump in to be rebuilt. My Mechanic said that he has worked on other 1960 210's that had an accumulator under the dash. Mine does not. Are there other options or modifications that could solve my problems.

Thanks