This may not be the right fourm, however I have a OS160 twin in my aircraft which has a engine cowl, thereby negating access to the carb fuel line.
I am using a Dubro tank with 3 fuel line connections.
1 line with clunk from tank to carb
2nd line with clunk to fill/empty fuel dot
3rd line is tank vent
When I fill the tank using an electric fuel pump fuel exits the vent line when the tank is full- normal.However fuel also runs down the line to the carb and floods the engine
I assume the electric pump is filling the tank faster than the fuel vent can handle and therefore over pressurising the tank and exiting fuel wherever it can
I was thinking of using a larger vent line
Any suggestion would be appreciated
Thanks