1968 Evinrude Speedifour, Starflite 85HP Service Manual, Page 16Get this manual
DESCRIPTION FUEL FLOW fuel system consists of fuel tank, fuel and carburetorThe fuel tank is pressurized, suction operateddiaphragmdisplacement type fuel the motor draws fuel from the tank and furnishes it to the carburetor through fuel filterCARBURETOR The carburetor is two-barrel, downdraft typeSee Figure 3-1jets fixedand only the low-speed jets adjustableCarburetor and magneto synchronized through adjustable linkageThe 85
INDUCED
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THEORV OF OPERATION
The carburetor is metering device for mixing fuel and airAt idle speed, an engine requires mixture of about parts air to part fuelspeed mixture is about 12:1 small chamber holds mits fuel from the fuel consumed the engineretor throat extend down the fuelfloat valve adtank to replace fuel as it is Metering jets in the into the fuel chamber
AIR PRESSURE