twin yamaha's from one battery

[jim@miss-em.com]

When I bought this boat it had twin yamaha 200s with two starting batteries. All of the electronics run from the stbd battery. If the port engine is used for trolling the stbd batt is drained after a few hours or less if it is foggy and the radar is on. The batt switch is the standard off-1-both-2-off.<br /><br />On my old boat the two Johnsons didn't mind being connected in parralel to one starting battery and the other battery was wired for house duties with a shorting switch between the two for an emergency. I broke out the alternator to charge through a West Marine battery combiner and connected the starters directly to the start battery. Been working great for years.<br /><br />Question is: can I do that with the twin Yamaha installation. Assuming one engine is started at a time from a single start battery and the house battery is a combo deep cycle/start for the electronics.<br /><br />Comments, suggestions... thanks.