Further to all this hydraulic pump stuff:

 

My original pump was circa 1989 and it had the small circular reservoir.  The fill/measurement method was thru a dipstick hole in the pump body where the dipstick was sealed with an o-ring.  The vent recommendation was to back the dipstick off by 1 to 1.5 turns (See the Lancair 235/320/360 POH).  If the reservoir was filled to the full mark, enough fluid would be expelled thru the vent to create a mess.  One solution was to create a standpipe vent and the other was to only fill the reservoir to the lo mark.   

 

When I installed a newer version of the pump a few years ago, I removed the larger reservoir and attached the smaller one to the new pump so that I didn't have to re-plumb the pump connections.  I also drilled a wee hole at an angle thru the dipstick head so that it could be snugged down and still provide the vent function.  I do not overfill the reservoir because it is usually topped up whilst the gear is extended (i.e. the rods are outside the actuators) - remember that the reservoir will have to hold more fluid when the gear is retracted.

 

Chris,

 

I don't know the ID/model of my currently installed pump but I will get that info the next time I have to crawl in the back and look at the  #@@$#%$$% pump.