Chrysler 6, 7.5, 180 Sailor Outboard Motors Service Manual, OB 3330, Page 26Get this manual
Subsection
_ FUELSySTEM
GENERAL
The fuel system, as defined by this manual, includes all the fuel components which are common to the system of the motorThe components included in the system are the Fuel tank, Fuel pump, Carburetor and Reed valve Troubleshooting the fuel system and brief description of the operation of the system is discussed in this subsection The reduction of air pressure causes the fuel to be pushed into and mix with the incoming air stream to form combustible airfuel mixtureThe airfuel mixture is admitted to the crankcase of the motor by reed type inlet valves The reed valve operates automatically, opening when the pressure in the crankcase is low enough so the outside pressure can over come the reed tension Figure 1
TROUBLESHOOTING OPERATION
The fuel tank is non-pressurized and suction operatedA diaphragm-displacement type fuel pump on the motor draws fuel from the tank and furnishes it to the carburetor bowlThe upstroke of the piston in the cylinder creates suction which draws air through the throat of the carburetorA restriction in the throat, called venturi, has the effect of reducing air pressure at this point (increasing air velocity) GeneralWhen motor will not start because of problem in the fuel system, it is very easy to run through an organized procedure in order to pinpoint the cause of the troubleObviously the fuel in the tank must reach the combustion chamberAny interruption of this flow will halt the operation of the motorGo through the following suggested check list to determine the exact cause of the trouble Checking Fuel FlowFirst make sure that there is a