second battery

[jdair101]

Hi All
In my C&C27mkV I currently have 2 27series batteries. I use the boat for club racing 80% of the time and think the second 27series battery is to big (heavy) and not in the best location for weight. I would like to down size the second battery for just a starting battery and then I can relocate it to a smaller better area. I would then only install the 2nd 27 series battery when spending the weekend on the hook. That way I would still have a battery for the engine if the other 2 are down in charge.
Now---- the engine is a Yanmar 1gm10 so does any one know if say a battery from a riding garden tractor would have the required cranking capability????

Thanks in advance

Jim

[scottyt]

i have a smaller battery for my starting but not a garden tractor one, i also have a 1gm and it starts just fine. although will 10lbs make a difference in a race, if it will i would think you could save it somewhere else

[jdair101]

its not so much as having a 10lb savings but moving that 50lb battery into the center and more forward in the boat, from the rear starboard side.
Its also having the extra power for weekending and still having a battery with full power for starting.

[hellosailor]

Jim, the question is how many amps or watts or horsepower is your starter rated for? And to some extent, how readily the engine starts, i.e. with one fast crank or a bit more work.

I can tell you that I have used a 17Ah AGM battery (sold for UPSes and emergency exit lighting) to start a Volvo MD7, which should be somewhat similar. Getting down to something that small counts as abuse--but if you really want to lighten the boat and just keep it as an "emergency starting" battery, it WILL do the job.

[timebandit]

You might want to give some thought about the chance of overcharging the smaller battery.