Fuel pressure issue.

Hello all, My 25cc Homelite Huffy will not suck the tank dry. I don't know what size tank mine is but it's the standard tank that came with the engine. It's an older one ('05) so I'm guessing the tank holds a pint or so. I've gotten it to do better by taking off the filter & putting a one size bigger fuel line on it & making sure the pick up part of it is at the most bottom part of the tank. The engine also has a new Zama carburetor on it so the fuel pump diaphragm should be plenty strong. Still, the engine will start bogging out at around 1/3 to 1/4 of a tank. I start using half choke to refire the engine (then choke off) & then it will run normal as long as it is kept under power. When coming to a stop the engine dies & struggles to start again. When the tank is full to 1/3 or so, no issues. Any thoughts ? ps...Just thought of this. Should the fuel return line be as low as the pick up line ? I'm wondering if once the return line is exposed to air if that somehow affects the situation ?

Just looked & indeed, the fuel return line only went half way down in the tank. Now it's all the way down. We will see if that is the culprit. Will let everyone know the test results.

That was the problem. The fuel return line needs to be as low as possible as well. It must allow an air pocket of some kind to occur once it gets exposed to air. Now the tank can be run practically dry with no issues. Live & learn.