1984-1986 Mercury Force 4HP Outboards Service Manual, Page 10Get this manual
Chedclng Fue AowFirst make sure that there is fresh properly mixed fuel in the tankOpen the ent of the fuel tank cap No Fuel 10 Combu.Uon Ch.mberRemove the spark plug and check its conditionA dry plug means no fuel is reaching the combustion chamberCheck fuel line for obstructionDisconnect fuel line at the carburetor inlet and check fuel flow by openi ng the valve and directing fuel nto suitable containerNo fueillow ind icates an obstruction in the line, usually the screen In the tankIf there is fuel fl ow then the trouble Is in the carburetorprobably stuck float alve or binding float
flooding wet spark plug means that the motor has been over-choked Go through the procedure for starting fl ooded motorShut off fuel valve, remove spark plug, and ground lead Spi the flywheel sever al times to remove excess fuel from the combustion chamberOpen the fuel valve, eplace the spark plugand then start the motor in the normal mannerCheck the fu el in the carburetor to see if water has gotten into itWater wHl appear as small beads or bubblesThe fuel tank is attached on top of the powerheadFuel from the tank is gravity fed to the carburetorThe tank Includes fine mesh screen which is attached to the fuel line fi tting on the bottom of the tankRemove fi tting and clean screen after flushing tank