57 Johnson 18hp press tank

[MThreeAd]

There has been alot of talk about the pressurized tank conversion to a non-pressure tank on the 57 18hp Johnson seahorse. We bought the engine last year and it cam with a tank with the 2-line fittings, 2-line hose and female fitting. The tank does not have a primer button to pressurize the tank, so it's a nightmare to get started. Used pressure tanks are running arouns 100 on ebay. Is there a way to use a bulb primer to pressurize the tank? I also need a new female fitting, but am thinking of using a direct hose connection to the male fitting on the motor to save 95 bucks.

Thanks.

 

[larky]

Re: 57 Johnson 18hp press tank

I have bypassed the female fitting on an engine that ran the two line system. worked fine just not that pretty. now the pressure tank i used was from an old jdx8 john deere snowmobile and had no primer button, i just installed a squeeze bulb primer and that gave me no trouble

 

[tashasdaddy]

Re: 57 Johnson 18hp press tank

is your tank like this one, if so the pump buttom is the silver plunger, at the end of the handle, the other type is just like it but has a black button. i just did a conversion, on a 58 35 hp i will cost about the same or more than a pressure tank, on ebay. sold this one for $80.

 

[F_R]

Re: 57 Johnson 18hp press tank

If it is an OMC tank, it does have the button as described by tashasdaddy. But just a side note here. The button DOES NOT pressurize the tank! It merely pumps fuel up to the motor to fill the carburetor. Once the carburetor has gas in it, you can start the motor and it will run till the gas is consumed. By then it will have pressurized the tank through the second (air) hose and it should continue to run.

 

[tashasdaddy]

Re: 57 Johnson 18hp press tank

if the cap is loose or the tank or any fittings are leaking air, it will not force gas to the engine.