1974 Johnson 40 HP Outboard Motors Service manual, Page 18Get this manual
DESCRIPTION FUEL FLOW
The fuel system consists of fuel tank, fuel pump, and carburetor The fuel tank is non- essurized, suc tion oper atedA diaphragm- displacement type fuel
pump on he motOr draws fuel from the tank and furnishes it to the carbu etor thr ough fuel filt r
T he carbureto throat Is fr equently called the "bar reL" Car buretors with single, double, or four barrels have individual metering jets, needle valves, thr ottle and choke plates for each ba.rrelThe two barrel carburetor Is red by single float and chamber while the four ba rrel model has separate float valve and chamber for each barrelINDUCED
VENTUR I
CARBURE TOR The carbur tor is inglebarre l, float feed typeThe high-speed Jet and low- speed jet are adjustableThe carbur tor has manual hokeThrottle linkage
is synchroni zed with the agnet by cam on the
THROTTLE