Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

On Tue, 18 May 2004 12:20:59 GMT, "Ernie"
wrote:

Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

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

Normal voltage while underway is in the range of 13.8 to 14.2

16 Volts is overcharging, and continued use will quickly destroy the battery.
The first guess would be bad wiring to the regulator, or maybe a bad regulator.
Before you do anything, check the water level in the battery - if you've been
running like this its likely down. If everything looks OK, you should check
with a digital meter to verify the voltage. Normally, regulators are set for
14.2 to 14.5 volts, and anything over 14.7 is considered overcharging. If it
really is 16 Volts, don't continue running it.

BTW, at 16 volts you should be able to smell the battery "cooking."





"Ernie" wrote in message
. ..
Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

Ernie wrote:

Is it normal for the battery gauge to read 16

If the 16 volts displayed is accurate it is a bit too high for
continuous charging of a lead acid battery, that is the "equalizing"
voltage. Check the charging voltage with a good quality voltmeter before
you start changing things because the cheap panel meters supplied with
consumer grade boats are not known for their accuracy.

If you have access to the battery while running and the battery is a wet
cell with removable cell covers (where you add water) look and see if
the cells are bubbling. If there are a lot of bubbles and/or you have
been adding a lot water then your charging voltage is probably high.

Rick

Ernie wrote:
Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

You should get an accurate measure of what the charging voltage is that
the alternator is putting out.

It sounds like your gage is showing 16 volts, but dashboard gages are
notoriously inaccurate. Can you put a multimeter on the battery
terminals when in operation? As somebody else posted, the voltage should
not be more that 14 or 14.2 tops.

Fair Skies
Doug King

Here you go

http://www.solectria.com/products/amphrm.html


DSK wrote in message ...
Ernie wrote:
Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

You should get an accurate measure of what the charging voltage is that
the alternator is putting out.

It sounds like your gage is showing 16 volts, but dashboard gages are
notoriously inaccurate. Can you put a multimeter on the battery
terminals when in operation? As somebody else posted, the voltage should
not be more that 14 or 14.2 tops.

Fair Skies
Doug King

Also Sprach Ernie :
Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

Regardless of the other replies, there are circumstances where charging
a charging voltage of 16-17 volts is perfectly normal and
expected. Specifically, many many older outboard engines, and even a few
newer but down-market ones, have low current unregulated charging
systems... in other words, they had a rectifier but no voltage
regulator. Since they are low current, topping out at 6 or 8 amps, they
typically won't fry your battery, so long as you make sure the water level
is topped up. Now, if you have an inboard or stern
drive, or a newer outboard with a regulated charging system, I'd do some
troubleshooting, starting by measuring the voltage at the battery with a
good digital voltmeter.

Dan

--
It's good to drink. It's good to laugh. But try to both at the same time
and you'll pay through the nose.

"Ernie" wrote in message
. ..
Is it normal for the battery gauge to read 16 when the boat is in
operation? The gauge only goes up to 18. The battery will be a year old
next month. Should I be concerned?

Ernie - More accurately, this is a volt meter, not a battery gauge. This is
nit-picky, yes, but an important distinction. When the motor's running, it
measures the output of the charging system, not the state of the battery
itself. Therefore, it's not the battery that is possibly "wrong" it's the
charging system. I say "possibly wrong" because...

As others have mentioned, the first guess is that your dashboard gauge is
inaccurate. You can test the battery, charging system, and therefore the
gauge, by getting a decent digital multimeter. The meter doesn't have to be
expensive, but I recommend digital because they're easier to read. Set it
to the volts DC scale, and test the charging system by putting the
multimeter leads on the main battery cables while the motor is running. As
mentioned, it should read "around" 14 volts (13.8-14.2).

When the engine is stopped, the meter (and your dash gauge) would simply
test the output of the battery itself. A fully charged 12 volt battery is
12.6 volts. This varies a little higher if it's freshly charged (it will
"settle" at 12.6). But, if it's actually at 12 - it's almost dead.

You can get a very cheap, little tester that will indicate (with various
colored LED's generally) if the charging system and/or battery is good or
bad. These LED's are, of course, set to indicate the ~14 threshold for the
charging system and the ~12.6 volt threshold for the battery itself. But a
multimeter is a handy tool to have and worth spending a few bucks on. I
carry the little cheap tester in my small tool box though.

Beyond that, I don't know how to trouble shoot or fix. I don't know from
rectifiers, stators, regulators, etc. But if you find that the multimeter
shows a good charging voltage of around 14 when the engine is running, you
can be pretty sure your gauge is bad, and you need to buy a new gauge. You
can find a lot of options on line from OEM to aftermarket and should be able
to exactly, or closely match your existing gauges. I'd suggest you
temporarily test the gauge before actually installing it. Gauge
installation is a pretty easy DIY if you're so inclined.

Cam

A fully charged 12 volt battery is
12.6 volts.

13.2

2.2 volts X 6 cells equals 13.2

"Gould 0738" wrote in message
...
A fully charged 12 volt battery is
12.6 volts.

13.2

2.2 volts X 6 cells equals 13.2


This is an often debated subject, because it depends on the type of battery,
temperature, aging, etc. In general for lead acid batteries:

Open circuit voltage Charge in %
12.6V and higher 100%
12.4 - 12.6V 75 - 100%
12.2 - 12.4V 50 - 75%
12.0 - 12.2V 25 - 50%
11.7 - 12.0V 0 - 25%
11.7V and less 0%


Eisboch