Jack,

 

Sounds like you may not be considering the volume taken up by the cylinder shafts. The level of fluid in the reservoir will be higher with the gear retracted. If you're filling the reservoir to the top with gear extended, this could explain your overflow. This is also the main reason that you need the vent in the cap. Without it, you'll pressurize the reservoir and possibly cause little vertical splits.

 

Bill Harrelson

N5ZQ 320 1,850 hrs

N6ZQ  IV under construction

 

 

 

 

 

Thanks, I forgot to mention, my ac has Outback Gear. Re- the inner gear doors vibrate with engine run, taxi, and probably in flight.  

Also:  New Item:
        The hydraulic reservoir at max fill always manages to puke out a bit of hydraulic fluid out the cap to the floor below.  Also, the right side of the reservoir has a vertical split about 2" long.   The split is tight and does not leak when on the ground.    After a flight, a small amount of hydraulic fluid does leak out split as well as from the yellow cap (with its 4 small relief spots to prevent cavitation). 

         I drilled a 1/16th hole in the yellow vented cap for additional ventilation, but no change.

         I used clear silicon for a neat repair of vertical but tight split and it worked for one flight, but then was attacked by the hydraulic fluid and failed and a slight weep appeared again.    Has anyone used a plastic epoxy sealant to repair in place?

          In the end, I believe the reservoir neck needs to be higher and with more ventilation to prevent air pressure challenges.

Jack Addison
N360JS