OMG - A boating question
 

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging circuit
for the cranking battery. The trolling motor battery gets charged at home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

OMG - A boating question
 

Lu Powell wrote:
I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit for the cranking battery. The trolling motor battery gets
charged at home prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the
same time while on the water, and use the trolling motor battery
without draining the cranking battery?


If your outboard's alternator has the "juice" and proper circuitry to
charge two batteries, yes. You could accomplish this with a good
multi-position battery switch. That way, when the outboard is running,
you could set the switch to "BOTH" and both batteries would charge, and
when you wanted the trolling motor only, you could flip the switch to
"2" or whatever the trolling motor is connected to on that switch.

Assuming your trolling motor battery is in the bow, you'd have to run
heavy, heavy battery cables to the switch in the stern. You'd also have
to remember to flip the switch.

This is not a great solution for you, though. In an emergency, if you
needed the outboard in a hurry, you'd have to remember to flip the
switch in order for the outboard to start.

You'd be better off adding another 12-volt battery at the bow for the
trolling motor so it would have two 12-volt batteries wired in parallel.
That would give you more trolling motor time. But you'd still have to
charge 'em up separately.

SW Tom probably could give you more specific and perhaps better
directions on this. But what you want to do is do-able.

OMG - A boating question
 

On Mon, 10 Aug 2009 08:51:15 -0400, "Lu Powell"
wrote:

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging circuit
for the cranking battery. The trolling motor battery gets charged at home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

The easiest solution is to use something called a "battery combiner".
It is essentially a voltage sensing relay that will connect both of
your batteries in parallel if the charging voltage exceeds a preset
level, and disconnect them when the charging voltage drops. The idea
is to allow charging both batteries when it's possible but prevent
accidently discharging your starting battery. It's a better
solution than a manual switch because it is all automatic with nothing
to remember.

Here are some examples:

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=1212673

OMG - A boating question
 

Lu Powell wrote:
I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit for the cranking battery. The trolling motor battery gets
charged at home prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the
same time while on the water, and use the trolling motor battery
without draining the cranking battery?

It's not likely that you would run your engine long enough to
significantly charge the deep cycle trolling battery. Small outboards
often don't have the charge capacity to charge two batteries. You can
test the capabilities by temporarily paralleling the batteries with
jumpers. I don't need to remind you that you need to be careful about
shorting things out and creating sparks.

OMG - A boating question
 

"Wayne.B" wrote in message
...
On Mon, 10 Aug 2009 08:51:15 -0400, "Lu Powell"
wrote:

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit
for the cranking battery. The trolling motor battery gets charged at home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

The easiest solution is to use something called a "battery combiner".
It is essentially a voltage sensing relay that will connect both of
your batteries in parallel if the charging voltage exceeds a preset
level, and disconnect them when the charging voltage drops. The idea
is to allow charging both batteries when it's possible but prevent
accidently discharging your starting battery. It's a better
solution than a manual switch because it is all automatic with nothing
to remember.

Here are some examples:

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=1212673


Thanks for the info. Looks like just the trick.

OMG - A boating question
 

"it's me, Jim" "j i wrote in message
...
Lu Powell wrote:
I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit for the cranking battery. The trolling motor battery gets charged
at home prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

It's not likely that you would run your engine long enough to
significantly charge the deep cycle trolling battery. Small outboards
often don't have the charge capacity to charge two batteries. You can test
the capabilities by temporarily paralleling the batteries with jumpers. I
don't need to remind you that you need to be careful about shorting things
out and creating sparks.

Thanks for the info. The outboard is a 70 hp Mercury. Do you know if its
charging capacity is adequate for two batteries as I described?

OMG - A boating question
 

"Wayne.B" wrote in message
...
On Mon, 10 Aug 2009 08:51:15 -0400, "Lu Powell"
wrote:

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit
for the cranking battery. The trolling motor battery gets charged at home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

The easiest solution is to use something called a "battery combiner".
It is essentially a voltage sensing relay that will connect both of
your batteries in parallel if the charging voltage exceeds a preset
level, and disconnect them when the charging voltage drops. The idea
is to allow charging both batteries when it's possible but prevent
accidently discharging your starting battery. It's a better
solution than a manual switch because it is all automatic with nothing
to remember.

Here are some examples:

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=1212673


Exactly what I have. Forget the brand, but was from West Marine. Have a
different relay setup, not marine for the truck to the camper. The other
advantage over a dual battery switch to charge the 2nd battery (I also have
a dual switch) is you can isolate the electronics from the starting battery
and avoid those voltage spikes when starting that damage electronics.

OMG - A boating question
 

"Calif Bill" wrote in message
m...

"Wayne.B" wrote in message
...
On Mon, 10 Aug 2009 08:51:15 -0400, "Lu Powell"
wrote:

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit
for the cranking battery. The trolling motor battery gets charged at home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

The easiest solution is to use something called a "battery combiner".
It is essentially a voltage sensing relay that will connect both of
your batteries in parallel if the charging voltage exceeds a preset
level, and disconnect them when the charging voltage drops. The idea
is to allow charging both batteries when it's possible but prevent
accidently discharging your starting battery. It's a better
solution than a manual switch because it is all automatic with nothing
to remember.

Here are some examples:

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=1212673


Exactly what I have. Forget the brand, but was from West Marine. Have a
different relay setup, not marine for the truck to the camper. The other
advantage over a dual battery switch to charge the 2nd battery (I also
have a dual switch) is you can isolate the electronics from the starting
battery and avoid those voltage spikes when starting that damage
electronics.


Thanks for the info.

OMG - A boating question
 

Lu Powell wrote:

"Wayne.B" wrote in message
...
On Mon, 10 Aug 2009 08:51:15 -0400, "Lu Powell"
wrote:

I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit
for the cranking battery. The trolling motor battery gets charged at
home
prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the
same
time while on the water, and use the trolling motor battery without
draining the cranking battery?

The easiest solution is to use something called a "battery combiner".
It is essentially a voltage sensing relay that will connect both of
your batteries in parallel if the charging voltage exceeds a preset
level, and disconnect them when the charging voltage drops. The idea
is to allow charging both batteries when it's possible but prevent
accidently discharging your starting battery. It's a better
solution than a manual switch because it is all automatic with nothing
to remember.

Here are some examples:

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=605576

http://www.defender.com/product.jsp?path=-1|328|51495|606044&id=1212673


Thanks for the info. Looks like just the trick.


Harry invented those. He just forgot, is all.

OMG - A boating question
 

Lu Powell wrote:

"it's me, Jim" "j i wrote in message
...
Lu Powell wrote:
I recently bought a used Champion brand bass boat. It has a battery
dedicated to the trolling motor that is not wired in to the charging
circuit for the cranking battery. The trolling motor battery gets
charged at home prior to a fishing trip.

Is there a simple fix that would let me charge both batteries at the
same time while on the water, and use the trolling motor battery
without draining the cranking battery?

It's not likely that you would run your engine long enough to
significantly charge the deep cycle trolling battery. Small outboards
often don't have the charge capacity to charge two batteries. You can
test the capabilities by temporarily paralleling the batteries with
jumpers. I don't need to remind you that you need to be careful about
shorting things out and creating sparks.

Thanks for the info. The outboard is a 70 hp Mercury. Do you know if its
charging capacity is adequate for two batteries as I described?


I don't, but you could refer to a service manual or ask Dave Brown or
Jim Granis. I'd want to know before I invested in a combiner, isolator,
or selector switch. Also you will need to decide weather you want to
keep the battery at the bow and run charging wires aft.