It is not all Group 31 batteries. Just the high capacity 925 CCA type.

Here is the service bulletin they got from their chassis supplier:
http://www.internationaldelivers.com...pdf/dyk128.pdf

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"johnhh" wrote in message
...
Someone help me out here. I always thought that the Group number just
specified the size/shape of the battery. Why would thhe size or capcity
affect its ability to hold a charge? Are you talking about a specific
manufacturer's battery? I can see how one manufactures group 31 my not,
but Group 31's in general?


"Glenn Ashmore" wrote in message
news:eC4Ef.15932$Dh.8853@dukeread04...
I was talking to an engineer with a local school bus manufacturer
yesterday about Rutu's progress. I mentioned that I was leaning towards a
high capacity Group 31 battery to use for the starter bank. More than the
4JH4 needs but would give me a lot of reserve. He replied that was a bad
idea on a sailboat. Seems that they no longer equip their school busses
with 925 CCA Group 31's because they have a very high self discharge rate.
They are great for regular highway use but school busses like sailboats
spend a lot of time with the engine off. The 620 to 700 CCA batteries
hold their charge much better and will last a lot longer in that type
service.

Just another tidbit to store away for future use.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com