hi i have a 1988 80 hp merc outboard for 2 years it run great, with a 2-3 yr old battery, sat. while driving the one side of the battery vent blew off, i put it on again and it blew off, i put in on again and it stayed on, the battery has a swelling in the sides, could i have to much voltage or just a bad battery, i have no gauges on this boat in came with none....boats runs well and i am not going to put that battery back as i am scared of the way it looks<br />bob in philly
