1981 Johnson/Evinrude 4HP Outboards Service Manual, Page 25Get this manual
LEAF VALVES aInspect the leaf valve assembly and disassemble if necessaryThe leaf valves must be free from all varnish and gum, and the leaves must be perfectly flat and without distortion so that they form perfect seal with the leaf plate baseSee Figure 3-12bDO NOT attempt to bend or repair damaged leaf; replace the complete assembly if damagedDO NOT under any circumstances bend or flex the leaves by handcReplace the leaf stop if any leaves are brokendBe sure fuel recirculc:tion orifices in intake manifold are clear and correctly installed CORE PLUGS aIf leakage occurs at core plug area, smart tap with mallet and flat end punch in the center of the core plug will normally correct this conditionSee Figure 3-13If necessary, remove core plug to clean out slow speed orifice holes When cleaning use caution not to enlarge holesSee Figure 3-14