How do I bleed the air from a tilt/trim cylinder??

I just had to have the hydraulic cyclinder on my tilt and trim reworked because it was leaking. I’ve reassembled the unit and now I am having difficulty getting sufficient fluid into it to make it work properly. It goes up and down but there is a notable delay as the fluid compresses the air and moves through the system. There is clearly air in the system. Can anyone tell me specifically what technique is used to purge the air from the system? It is a single cylinder unit for a Merc 9.9 Bigfoot. Thoughts?

can’t tell you 100% since I’ve never worked on that one, but i rebuilt my Showa and all the air gets bled through the fill cap on the resevoir. Trim it up all the way and crack the cap a little and you should hear the air coming out. you may need to do this several times.