Hi, I was wondering why my leafblower gas tank builds up pressure when I run it.It will run for so long then it will start to surge a bit and then I notice fuel leaking out of the hole in the center of the fuel cap and when i open it(very slowly,that is)there is so much pressure built up in the tank and the fuel just wants to shoot out.thank you!

 

I'm not sure how much pressure we're talking about here. Some is normal. The vent in the gas cap should not allow fuel to escape.

 

were talking alot of pressure,yes some pressure is ok especially when you are moving it around and sloshing the gas back and forth.i thought it was a vent problem where the venting is allowing air to get into the tank,so that it does not create vacuum.but if gas is leaking from the vent hole it must mean that there is pressure building up inside the tank.when i remove the cap,there is a rush of fuel trying to escape-what is the problem here?

 

Why hasn't anyone answered my question?

 

I didn't see your last reply.

You're correct about what the vent does. If it is building that much pressure, I'd say your fuel pump is picking up air and putting it into the tank through the return line.