OMC engine tuner red shrader valve

[Timeking]

My dealer gave me a fitting that goes on the shrader valve by the choke on a 2000 150hp Johnson carbed, to shoot in the OMC Engine Tuner. I can get the cover off the carbs, and hook up the adapter to the shrader valve, but ... What is that red lever for?

 

[Daviet]

Re: OMC engine tuner red shrader valve

I think the red lever is to prime the motor manually. Reposition the lever (rotate) to switch from auto prime (choke) to manual prime.