Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 396Get this manual
MAINTENANCE
7- Check all electrical parts on the engine and electrical fixture or connections in the lower portions of the hull inside the boat to be sure they are not of type that could cause ignition of an explosive atmosphereRubber caps help keep spark insulators clean and reduce the possibility of arcingStarters, generators, distributors, alternators, electric fuel pumps, voltage regulators, and high-tension wiring harnesses should be of marine type that cannot cause an explosive mixture to igniteONE FINAL WORD
Before putting the boat in the water, TAKE TIME to VERIFY the drain plugs are installedCountless number of boating excursions have had very sad beginning because the boat was eased into the water only to have water begin filling the insideKeep your gas tank full, the fuel pump pumping, the spark plugs sparking, and the pistons, well, keep them working too