tire valve on 40HP johnson (1990)

[TerryMSU]

I am curious. I have a 1990 40HP Johnson and I am wondering about something I noticed on it. The motor has (on the starboard side) a schrader valve (a car tire valve) on it with a small red pointer attached to it. What is the valve for and what is the function of the red pointer?

Thanks,
Terry

 

[22ISLANDER]

Re: tire valve on 40HP johnson (1990)

That valve is your "tuning" port. It is used for hooking up a can of de-carboning solution that is sold at OMC dealers. The red pointer straight up means it is open, 6 o'clock means closed.

These ports are a great idea, and work very well in keeping your engine clean on the inside.

I'm suprized other with greater knowledge of this have not chimed in, but soon, somebody will.

 

[rickdb1boat]

Re: tire valve on 40HP johnson (1990)

That is the primer solenoid. Consider it a modern day choke. When you have the ignition key in the ON position and push the key switch in, it injects a stream of fuel directly into the cylinders to enrichen them for a cold start. When cold starting the engine, you would pump up the fuel primer bulb, turn the key to the ON position and while holding it pushed in, crank the engine over until it starts. The red lever is for manually "choking" it in case the electrical system is dead and you have to pull start it. The schrader valve is used for injecting engine tuner and for fogging the engine before storage..

 

[tashasdaddy]

Re: tire valve on 40HP johnson (1990)

this picture is the normal operating position, so that the key activates the solenoid.