1975 Evinrude 2HP Model 2502 Full Factory Service Manual, Page 18Get this manual
3-2 OEseRI PTiON The fuel system cons ists of fuel tank mOWlted on the power head, a
fuel filterand carburetorth carburetor
Fuel flows, gr avity-fed from the tank to
CARBURETOR
The carburetor is single-ba rrelfloat feed typeThe high and lows peed jets ar adjus tableThe carburetor has manual chokeThrottle linkage is ynchronized with the magneto by cam on the magneto armature plateTHEORY OF OPERATION The carburetor is metering device for mixing fuel and airAt idl e
speed, an engine equires mixture of about parts air to part fuelHigh peed miXture is about 12;],
INDUCED LOW
A small cha mber holds the fuelA float valve ad mits fuel from the fuel tank to replace fuel as it is consumed by the engineMeterin jets in tbe carbur etor tbroat extend down into the fuel chamber The upstroke of the piston in the cylinder creates suction that draws ir through the throatA estriction in the throat, called venturi, has the effect of educing ai pr essure at this point, by controlling air
ve lOCi ty
The diffe ential in throat and cha mber air pres sures Causes the fuel to