Christine wrote:
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


Use your voltmeter and see if there is a current discharge at the
voltmeter.

Use your voltmeter and see if there is a current discharge at the
voltmeter.


Or temporarily connect your VOM between the positive battery terminal and
the positive battery cable and check to see if there is any appreciable
current flow while the boat is in its stored condition, with everything
allegedly turned off. This will tell you if anything is drawing the battery
down while it is on the trailer or in the slip. Don't try and start the
engine with the VOM is in line with the battery cable. The operative word
was temporarily. Only just a test for static draw while at rest. If you do
notice any amperage being drawn in this situation, you will need to manually
disconnect each bit of electronics on the boat to find the offender.