evinrude 50 hp, gas tank pressure, power surges

[cheeko]

Hi Guys:

I am new at this and did not know but I often left my plastic fuel tank pressure release valve shut tight. Sometimes the hot days expands the tank tightly out and sometimes I forgot to undo it will I the tank implode while the engine is running. Is this really bad for the fuel pump?

MY problem here is that since yesterday, the engine surges when it is at full throttle, this is the cause of the pressure release valve? The problem still remains even after I release the gas pressure valve. Did I mess up the gas pump.

What can I do or look into solving the surging problem? The problem does not exist at lower throttle but I think it is struggling a bit now.

the motor is a 1989, 2 cyl, carb
Hellpppppp!

cheeko

 

[tashasdaddy]

Re: evinrude 50 hp, gas tank pressure, power surges

disconnect the fuel line, when not using, the sun heats the tank, and the pressure is transferred to the carb float needle valve, and to the fuel pump diaphram. the tank vent has to be open when the motor is being used. the fuel pump cannot pump fuel out of a vacuum. put a cover on your boat when store, the sun is killing all of the interior. are you doing damage Yes. it is not a pressure relief valve. it is an air vent so the fuel pump can pump fuel.

 

[cheeko]

Re: evinrude 50 hp, gas tank pressure, power surges

Thanks Tahshadaddy

How baot the surges< what causes that? where should i start looking into?

Thanks

cheeko