1996 Johnson Evinrude "ED" 40 thru 55 2-Cylinder Service Manual, P/N 507124, Page 66Get this manual
Description of Fuel System 1The fuel pump is of the diaphragm-displacement type and is operated by changes in crankcase pressureAlternately, suction and pressure in the crankcase are transmitted to the pump diaphragm
rn 2.control engine speed and power output fuelvarying the The carburetors meter and distribute the consumedby They
intake charge densityTo react correctly to wide range of operating conditions, the carburetors have multiple fuel mixing circuits[]] 3The unit is combination mechanical fuel and oil pump, powered by crankcase pressure and vacuum pulses, which responds to various engine power settings by injecting the proper amount of oil into the fuel systempump incorporates circuit that warns the operator The of "NO OIL" situation4Mixture enrichment for cold starting is controlled by either manual primer (rope models) or fuel primer solenoid (TE, TTL and remote control models)