2005 SO Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 111Get this manual
FUEL SYSTEM CARBURETOR OPERATION
Manual Starter System
When starter knob is pulled, fuel is drawn into the starter circuit from the float chamberStarter jet meters this fuel, which then flows into fuel pipe and mixes with the air coming from the upper part of float chamberThe mixture, rich in fuel content, reaches starter plunger and mixes again with the air coming through passage extending from main boreThe two successive mixings of fuel with air produce the proper fuelair mixture for starting when the mixture is sprayed out through starter outlet port into the main bore1234567Float chamber Starter jet Fuel pipe Float chamber Starter plunger Mainbore Starter outlet port