Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 313Get this manual
ELECTROMATIC SHIFT 4- Battery Check: Begin with thorough check of the batteryMeasure the gravity of the electrolyte in each cell by withdrawing only enough to lift the floatTake the reading at eye levelA fully charged battery cell should read 1.280; at half-charge, 1.210; and dead battery will read only 1.150If the electrolyte level is low, bring it up to full level with clean clear waterNEVER ADD ACID to battery cellIf water is added, it is not possible to take an accurate reading until the battery has been charged for few hours5- Battery Voltage: Check the total battery voltage for full 12 voltsClean any corrosion from on or around the cables and terminalsRemove the cables, clean the posts until bright metal is visibleScrape out the inside of the battery terminals, then connect and tighten them securely6- Amperage Draw Check: Turn the ignition switch to the ON position and observe the amperage reading on the dash am meterIf an amm eter is not installed on the dash, one must be temporarily connected to the system for this test by first removing the wire marked BAT from the key switch, and then connecting the ammeter in