1997 Johnson Evinrude "EU" 9.9 thru 30 2-Cylinder Service Manual, P/N 507263, Page 37Get this manual
Preseason Service 1Check gearcase lubricationIf leakage is evident, gearcase seals may need attentionCheck lubricant level in power trimtilt reservoirSee Lubrication, this section
& 2Apply light coating ofOlVlC Electrical Grease to the ribbed
portion of the spark plug ceramics and the opening of the spark plug coversConnect spark plug leadsMake sure spark plug boots are not cracked or torn
& 3Check water level in battery, then chargeWhile the battery
is charging, the acid solution inside the battery gives off hydrogen gas wh ich can explode if ignited by spark or open flameIf hydrogen gas is not able to leave the battery (vents are clogged), the battery itself may explodeTherefore, when charging batteries, make sure that battery is vented to atmosphere and lots of fresh air is in the areaMake sure no sparks or flames are presentDo not short across battery terminals to check battery conditionInstall and connect battery