check on a battery isolator then you can do without the switch.

If both batteries are the same age and type they will come close enough to
charging equally with the switch in the both position. Wait till you price
the wire you will need too.

And thus why I still have one battery.

"Bryan" wrote in message
om...

"Wayne.B" wrote in message
...
On Sat, 21 Jan 2006 13:55:11 GMT, "James" wrote:

If you really want two batteries I would recomend they be the same. That
way they will come close to charging equally when the battery switch is
in
the both position.

Thats what I do on my 24 footer and it works fine. I usually start up
and run in the "both" position so that everything gets charged up. If
we stop to anchor, I switch to the #2 position until ready to leave.


Do you have any arrangement to make sure both batteries charge the same or
do you do alright with the practice you described? I didn't realize I
would have to deal with more issues than a second battery and a switch!

" JimH" jimh_osudad@yahooDOT comREMOVETHIS wrote in message
...

"Bryan" wrote in message
et...

" JimH" jimh_osudad@yahooDOT comREMOVETHIS wrote in message
...

"Bryan" wrote in message
t...
I'm thinking of adding a second battery to my 18 foot bowrider. I want
to use one battery for the engine and one for the stereo and lights and
air pump and ...

I don't want to lose my engine starting ability due to a battery that's
been run down using accessories.

My first battery is a Marine/RV Cranking type (I can't read the
labeling to know what it's amp hour rating is).

What type should my second battery be?

Thanks


A deep cycle with decent CCA's.

Care to explain your answer or should I just blindly accept your advice?
; ) Oh yeah, and I don't know what CCA's are or maybe I do, I'm not sure.


You said you will be using the second battery for accessories.....that is
what a deep cycle battery is designed for.

You can also combine engine cranking ability with the accessory draw
demands by purchasing a deep cycle battery with a decent CCA (cold
cranking amps) rating.

I would consider a Group 27 deep cycle battery with as high as CCA's (650
minimum) as you can find.

Good links:

http://www.windsun.com/Batteries/Battery_FAQ.htm

http://www.windsun.com/Batteries/Battery_FAQ.htm


Get a 2nd Deep cycle / starting battery. They will not be rated in CCA, but
MCA's. Same thing, but the MCA's will be more. CCA's are at some freezing
temperature and MCA are at 32f. Get a Guest Dual battery switch so you can
switch between eh 2 batteries for starting. You can flip the switch to run
off one battery or the other to keep them both charged, or do as I did and
installed a Battery combiner so when one is charging the other is also. I
have one from West Marine, and Sure Power makes one also, a mdl. 1315, but I
do not know if it is for mariner use. You then also have to add a battery
switch to disconnect the 2nd battery completely from the electronics.