1955 evinrude 25hp wont stay running unless fuel primer bulb is being pushed. Help please

[zach bice]

Hello just bout this boat, its has a 1955 evinrude 25hp outboard shortshaft motor on it. when i got it, it had a metal tank in order to it the fuel going into the lines the tank had to be at like a 45degree angle rain okay once the tank was on an angle. I switched to a plastic tank and the motor runs for a few mins then dies if i prime the bulb it fires up and runs then dies again, if i stay there and keep priming the blub it stays running, not sure where to start looking. i have replace the lines to from the tank to the motor i have also replaced the primer bulb any idea where to start looking for a leak or any suggestions would be helpful. Thanks

 

[racerone]

Sounds like someone converted from a pressure tank ( double line hose ) to a single hose with a fuel pump.-----So without pictures or hands on I can't tell.----Not everyone does this swap correctly.

 

[zach bice]

Sounds like someone converted from a pressure tank ( double line hose ) to a single hose with a fuel pump.-----So without pictures or hands on I can't tell.----Not everyone does this swap correctly.

What kind of picture would help? i dont think there is a fuel pump. the fuel line goes to a clean filter that is mounted to the carb therefor i dont think it has a fuel pump. should i just keep running the (double line hose ) aka metal tank

 

[McGR]

If indeed your motor doesn't have a pump, then you need to use the double line system and original pressure type tank. These motors pump fuel by pressure provided from the engine crankcase, hence the second line connected to the motor and tank. Typical single line type tanks are made for motors that have pumps and have the ability to draw fuel from the tank.

 

[racerone]

What ?????----You are talking about a plastic tank and a primer bulb.-----Then we are talking like you still have a steel tank and the pressure system without a fuel pump.----Pictures needed as I know these motors very well ( have one myself ) but I am confused by your set-up !-----You can not run with a single line hose without a fuel pump.