Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 47Get this manual
REED or other wind instrumentAt rest, the reed is closed and seals the opening to which it is attachedIn the case of an outboard engine, this opening is between the crankcase and the carburetorThe reeds are mounted in the intake manifold, just behind the carburetorActual Operation The piston creates vacuum and pressure as it moves up and down in the cylinderAs the piston moves upward, vacuum is created in the crankcase pulling the reed openOn the compression stroke, when the piston moves downward, the reed is forced closedReed Designs Cross-section of cylinder reed in the crankcaseto
SERVICE
BROKEN REED VALVE
A wide range of reeds, reed plates, and reed box installations may be found on an outboard unit, due to the varying, designs of the enginesAll installations employ the same principle and there is no difference in their operationBroken Reed
illustrate