This too is a problem I had on my 282 Sailfish on the 2 battery bank. I'll go through the search process and you can see if there
are any similarities. Talked to the local service manager (Scott) before proceeding and got ideas from him. I replaced batteries
(under warranty) first thinking that was the problem and the problem continued. The troubleshooting got serious after that.
Removed and cleaned corrosion off the buss bars. I even disassembled and cleaned the main buss bar and lugs in the battery compartment. Having a Dremel tool and brushes makes polishing easier.
1. There are a multitude of miscellaneous wires attached to the positive terminals of each battery. They skinny ones power
all the accessories or buss bars around the boat. The first step is to try and identify which is which. Most have factory labels,
you just have to interpret the rest. All was done with the battery switches in the OFF position.
2. The bilge pump/float switch was the first place to start. We took it out, cleaned, reinstalled and it works.
3. The next number 8 size wire was for the windlass. Disconnected it from the battery and put a multimeter between it
and the battery positive terminal and looked for a power draw. Got a .2 reading. While this is nomimal, Scott said it is
enough to draw down the battery if not used for an extended time. Solved this by putting a lug on the battery that had
a screw terminal and now just hook up the windlass cable when it is needed. This is a PIA but it does solve the small drain
problem. This does not solve the original problem, but it is a fix.
4. In tracing the other wires, found 2 more that were HOT when the switches were OFF. As previously mentioned, one
traced to the overhead radio box and was not hooked to anything. Solution: disconnected it from the battery. Was not
using it anyway.
5. The second wire was more interesting. It traced to the AM/FM stereo on the cabin. It was separate from stereo and the
purpose was to remember the pre-sets on the stereo when battery power was turned off. This was drawing about .5A even
though the stereo had been removed. The wire ran from a positive terminal over to the 10A push-button breaker on the
switch panel and back into the cable runs on the boat. It was a pain to trace. Solution: disconnect from battery. Also
replaced the 10A breaker since I had the panel off.
6. The fourth possible drain, and the most probable, was the battery charger. There are cables coming out of the charger
that span both batteries. There was a nomimal power drain (.3A) showing. Scott said if corrosion forms inside the charger, then
it can start a drain on the batteries. The charger is connected to the shore power. I don't use/don't need it. The engine alternators
do the job. Solution: disconnect the 3 wires from the charger.
7. All together, these 4 problems were doing enough to cause the batteries to drop from 11.90 volts at the end of the day
to under 8 volts in a week. The engines would not turn over.
8. A multineter is your friend and knowing how to read one is important. It can show small power draws and makes
checking continuity a breeze.
These are the problems I had and the solutions. I only disconnected cables that were not being used. All other wiring was
checked for nominal voltage drains and was found to be zero.
I have learned more about the wiring on the boat than I care to know. The problems do show that small things can ADD UP
to cause a major problem.
Good luck.
