Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 97Get this manual
TROUBLESHOOTING If there is no fuel discharged from the line, the check valve in the squeeze bulb may be defective, or there may be break or obstruction in the fuel lineIf there is good fuel flow, then crank the engineIf the fuel pump is operating properly, healthy stream of fuel should pulse out of the lineContinue cranking the engine and catching the fuel for about 15 pulses to determine if the amount of fuel decreases with each pulse or maintains constant amountA decrease in the discharge indicates restriction in the lineIf the fuel line is plugged, the fuel stream may stopIf there is fuel in the fuel tank but no fuel flows out the fuel line while the engine is being cranked, the problem may be in one of several areas: 1- Plugged fuel line from the fuel pump to the carburetor2- Defective a-ring in fuel line connector into the fuel tank3- Defective O-ring in fuel line connector into the engine4- Defective fuel pump5- The line from the fuel tank to the fuel pump may be plugged; the line may be leaking air; or the squeeze bulb may be defective6- Defective fuel tank7- If the engine does not start even though there is adequate fuel flow from the fuel line, the fuel inlet needle valve and the seat may be gummed together and prevent adequate fuel flow