I have the F3680, same machine but little larger motor.
A WSM is so helpful. I also have the exploded parts diagrams manual. Very helpful to learn where everything is as well as understand all the parts. A dealer can get this ordered for you. About $30.
Not sure, when you say immediately shuts down, this may not be the issue but will throw it out here. These machines have 2 fuel filters. I had running problems when these were not changed with the correct frequency. Fuel can bleed threw slowly allowing a start but once started, enough fuel cannot pass quickly enough thus the shutdown. Maybe that is happening? Probably a long shot.