Vessel: 1999 Maxum 1900SR
Engine: 4.3l Mercruiser w/Alpha I drive
Issue: Battery is being drained by ____(something).

Details: Installed a new 550 CCA Marine Battery about 3 weeks ago. Ran
great when first installed. Boat sat for 2 weeks, tried to start - "click".
Nothing. Was able to jumpstart from the truck, ran it for about 15 min top
charge. Voltmeter on the boat dashboard reads 10.5 volts. Hand-held
voltmeter at battery reads 13.98; test at alternater reads the same. Took
battery back to dealer & had tested. Battery OK, fully charged.

So, I think the alternator is OK. No visible frayed wires & such. My gut
tells me that the voltmeter in the dash is suspect since it reads
differently than the hand-helds.

Any sugggestions as to what could be draining the battery or anything else
typically to look for?

Thanks,
Mike