1995 Johnson/Evinrude Outboards 40 thru 55 2-Cylinder Service Manual, Page 268Get this manual
Specific gravity will vary points (0.004) with every 10 (6 C) temperature changeFor each 10 (6 C) below 80 (2]0 C), subtract points from hydrometer readingFor each 10 (6 C) above 80 (2]0 C), add points to hydrometer readingAfter correcting to 80 (2]0 C), interpret readings as follows: All cell readings uniform and above 1.225 specific gravity indicates battery is serviceable, but may require charging All cell readings uniform and below 1.225 specific gravity, charge fully and retest Variation of more than 30 points (0.030) specific gravity between any two cells, indicates battery condition is questionableRecharge and retest before replacing battery3Capacity Test Satisfactory capacity tests can be made only when the battery electrolyte equals or exceeds 1.225 specific gravity at 80 F (2]0
4Terminal Voltage Test
ill procedures