Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 12Get this manual
Out-ol-Season Battery Storage 1Remove battery as soon as possible and remove all grease, sulfate and dirt from top surface2Cover plates with distilled water, but not over 316 in(5mm) above perforated baffles3Cover terminal bolts well with grease4Store battery in COOL, DRY place in dry carton or box5Remove battery from storage every 60 daysCheck water level and place on charge for to hours at amperesDO NOT fast charge
8Continue flushing until water being discharged becomes clear (5 minutes for engine operated in salt water) 9Stop engine, turn water off and remove flushing attachment from gear housingIMPORTANT: While and after flushing, keep motor in upright position until all water has drained from drive shaft housing to prevent water from entering the powerhead via drive shaft housing and exhaust ports
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