Re: 2.5 seahorse carb problem
The gas line from the tank usually connects to a fuel pump diaphragm. Which is on the port side of the motor when mounted on a boat. The gas line then runs from the fuel pump diaphragm to the port side of the carburetor. (If you take the carburetor apart you will be able to follow the flow easier.)<br /><br />Fuel comes into the carburetor at this spot and travels through a cavity in the carburetor to the needle valve. Inside of the bowl is a float that controls the open/closed position of the needle valve. If the float is all the way up to the top of the bowl (meaning the bowl is full) the needle valve will be closed and therefore no gas is needed and does not flow. If the float is anywhere but at the top of the bowl (meaning the bowl is emptying) the needle valve will be opened and therefore more gas will flow into the bowl filling it. So gas comes into the carburetor goes past the needle valve when open and enters into the bowl. The fuel is then stored in the bowl until it is vacuumed up one of the jets and into the motor. You may have one or 2 jets (Main Jet and a Idle Jet) I believe that on the 2.5 you only have one jet that acts as the main and idle jet. With the choke and throttle plate both in their closed position you will notice a hole at the bottom of both the plates. The piston movement pulls outside air into the carburetors throat through the holes in the lower part of the plates. The air passes over the jet, which creates a vacuum that sucks the fuel from the bowl and delivers it into the motor. That is the basics of how the gas travels from the tank to the motor.<br /><br />If you can take a picture of the exact part it might help. Im not sure if you are referring to the fuel pump diaphragm or a part on/in the carburetor like the needle valve.<br /><br />Here is a pic of what a needle valve looks like
needle valve They are typically less than 1 inch long
