Overflow Trim

First and fuel line cutter?
Someone gave me a career-no cutting chain. It is a Ryobi 780. I can not find the manuals Online. The primer is dry rot, and therefore the fuel lines. I spent all primber six dollars for a new bulb and 2 feet of line fuel. How do the lines between tank primer bulb, and carbohydrates? The tank has two holes, one for the fuel to run the motor and one for the "spillover" of carbohydrates. The pear is a two hose barbs, is marked "IN." There are 2 barbed in carburetor. I have no carburetor to work with me, but I think it's a beard at the top of the carbohydrates and a beard is at the bottom of the container. How I can Use fuel lines between the tank, the bulb and carbohydrates? Could black seal RTV be good to put around the fuel line enters the plastic fuel tank?
The fuel line is tight in the holes in the gas tank, so there is no need for a sealant around them. Here is a site that explains how to replace them. Pera only gas pumps in the carburetor and returns to the tank and has a check valve on it for that the gas tank, says in the bulb. Good luck http://www.ehow.com/how_6396290_replace-line-ryobi-gas-trimmer.html

