Reef octopus skimmer air intake issue

[anarchy]

I have a reef octopus nwb 150 skimmer with an OTP-2000 pump. Any time i turn my skimmer off and turn it back on the air intake wont automatically start pulling air. I have to blow into it to start the suction. Any idea what the problem could be? Ive replaced the impeller and soaked and cleaned everything in vinegar and nothing has worked

 

[Reefing Madness]

 

[Reef Junky150]

Upgrade to the new pumps, they auto start. The old style won't 90% of the time. I have the same skimmer for 9years now. Pumps finally died. When I replaced them the new impeller design helps them auto start. Not just sit and chatter.

 

[Reef Junky150]

 

[Reef Junky150]

http://www.coralvue.com/reef-octopus-otp2000-circulation-water-pump