how to purge air from surge pipe?

I have been running a Carlson surge on my tank for a few year now. I have been able get the it quit by putting a small pipe on the overflow of the flush valve.





However, i have been unable to remove the air in the pipe before the syphon kicks in.







I have tried venting the pipe but it only reduces it a bit. the problem I find is the force of the syphon push the air through the pipe instead of out the vent.



Anyone have any ideas I could try?