Outboard Overcharging... (long)
 

I'm not aware of specific differences but there are differences
between manufacturers and between battery types, i.e., starting
batteries vs. deep cycle. I'm guessing a little but my sense of it is
that a smaller battery would be more likely to achieve a 100% charge
and float up to the kind of voltage you're seeing. It might be
interesting to connect a good size marine battery like a 4D in
parallel and see what hapens to the voltage. My guess is that it
would drop as the larger battery should be more capable of absorbing
charge.

I was thinking along the same lines too and bought a 1000 CCA battery. The
motor specs call for a minimum of 360 CCA. So far it has done the opposite of
what I thought would happen.
Someone in the electricial engineering group suggested that I may have been
wrong buying a larger battery because its not discharging from the low starter
demand (the motor runs perfect and usually starts instantly). and the bigger
battery has more resistance.

Outboard Overcharging... (long)
 

"CCred68046" wrote in message
...




If this does not work I am going to try a battery combiner and
let it charge my deep cycle trolling battery too.

that sounds like the easiest and best approach!

If the outboard can only drive 5 amps it shouldn't take much of a battery
bank to provide that kind of load. If you have the current to spare, there
is no reason not to charge the trolling battery.

I suspect that the higher voltage is because the new battery is fully
charged, where your previous battery was always at some level of discharge.
An experiment you might want to try would be to drain the battery a bit and
then hook it up. Hook it up to your trolling motor for about 20 minutes and
then swap back.


Rod

Outboard Overcharging... (long)
 

On 09 Jun 2004 05:08:44 GMT, obull (CCred68046)
wrote:

This problem comes up over and over again in the newsgroups and boating boards
and NO ONE has answered it...

A lot of older outboards came with un-regulated charging systems and I have
one.
I read about people reporting that their voltage had risen to 16+ volts. Last

snip

o be an answer to this. Could something
cause three VOM's to read incorrectly?


You kind of helped me answer a question I had not asked. Thanks. I
recently bought two 6 volt solar cells from Walmart and wired them in
series to charge my battery on my little boat. Since my motor does not
have any hookups to charge the battery I had to think of something.
Nothing sucks worse than being out fishing at night and having your
lights go out. Since I only use my boat for a few hours each week the
sun has plenty of time to recharge from what little use I give it.

But what had me worried was that in bright sunlight the cells were
putting out a combined 16 volts. I thought that might fry my fish
finder and although it is a cheap one, I can't afford to replace it.
Since reading the replies to your post I feel more assured that 200
milliamps at 16 volts from a couple solar cells are not a serious
threat to a fish finder. If your equipment can handle 16 volts at 5
amps I should be in the clear. Or am I wrong?

Outboard Overcharging... (long)
 

On Thu, 10 Jun 2004 23:53:12 GMT, Ookie Wonderslug
wrote:
Since reading the replies to your post I feel more assured that 200
milliamps at 16 volts from a couple solar cells are not a serious
threat to a fish finder. If your equipment can handle 16 volts at 5
amps I should be in the clear. Or am I wrong?

========================================

You should be fine, 200 milliamps is not enough to damage the battery.

Outboard Overcharging... (long)
 

If your equipment can handle 16 volts at 5
amps I should be in the clear. Or am I wrong?

Mine has been going like this for almost 3 years now. Based on my experience
you will be OK.

Outboard Overcharging... (long)
 

Clamp it with a Zener Diode somewhere on the 12v output line. All excess
current will bleed off.

-W

Outboard Overcharging... (long)
 

Clamp it with a Zener Diode somewhere on the 12v output line. All excess
current will bleed off.

Thanks Clams,

I know I could regulate it easily. You are an old Merc fan and you know how to
fix it so you must have run into this before. What I am looking for is the
reason its doing this now after it ran fine all those years. Everything is
still in spec electrically. I really find this interesting. All the posts on
the web about it and no one can or has answered it yet.

Outboard Overcharging... (long)
 

"CCred68046" wrote in message
...
Clamp it with a Zener Diode somewhere on the 12v output line. All excess
current will bleed off.

Thanks Clams,

I know I could regulate it easily. You are an old Merc fan and you know
how to
fix it so you must have run into this before. What I am looking for is
the
reason its doing this now after it ran fine all those years. Everything
is
still in spec electrically. I really find this interesting. All the posts
on
the web about it and no one can or has answered it yet.


The biggest reason that voltage climbs so high on an unregulated system is
that the battery is too small a capacity, and/or is a sealed or "maintenance
free" version. You want a "flooded cell" battery, the largest you can fit
and afford, to run your boat's electrics. Get a group 27 heavy duty battery
and you won't have any problems. A cheaper way of regulating the charging
system is just to use an additional battery in parallel to absorb the extra
charging.

Years back we told customers to run the boat lights all the time and have
the dash lights wired into the key switch so they were always on. That also
cut down on the condensation inside the gauge faces.

Bill Grannis
service manager

Outboard Overcharging... (long)
 

"Ookie Wonderslug" wrote in message
...
But what had me worried was that in bright sunlight the cells were
putting out a combined 16 volts. I thought that might fry my fish
finder and although it is a cheap one, I can't afford to replace it.
Since reading the replies to your post I feel more assured that 200
milliamps at 16 volts from a couple solar cells are not a serious
threat to a fish finder. If your equipment can handle 16 volts at 5
amps I should be in the clear. Or am I wrong?


It's extremely unlikely that the solar cells will be putting out 16v with
any kind of load on them. I'm betting that you measured 16v with no load
(open circuit). You'll be fine.

Jack

Outboard Overcharging... (long)
 

The biggest reason that voltage climbs so high on an unregulated system is
that the battery is too small a capacity, and/or is a sealed or "maintenance
free" version. You want a "flooded cell" battery, the largest you can fit
and afford, to run your boat's electrics. Get a group 27 heavy duty battery
and you won't have any problems. A cheaper way of regulating the charging
system is just to use an additional battery in parallel to absorb the extra
charging.

Hey, good to see your still in the group Bill!
I have tried several batteries... I'm currently running a group 27 1000cca. I
have tried 3 BIG non maintenance free batteries. Everyone of them did the
same thing. The factory service manual calls for a minimun of 360 CCA. It
seems like Im not running them down enough to give the charging system
something to do. I just bought a 420 CCA to try that because a few of the guys
in the electricial engineering group said the bigger battery has MORE
resistance to charging once its full and is adding to the problem.
I gave up on electrical "experts", they cant agree on this at all. I'll trust
your experience on this. Money is not the problem. If you know of a specific
brand and model of battery that will work I will try one.
Now for a good laugh... I just happened to see another motor like mine Saturday
at the dock and talked with the owner... Now get this.. this guy didnt have a
clue about his old boat but he let me look at it. The thing is running a
perfect 14.5 volts and he's running a 520 CCA MAINTENANCE FREE battery.
ARRRRRRG.