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On a somewhat related issue, I have an ammeter and voltmeter connected to my
Yamaha 9.9 4 stroke. It is relatively new, but I think it was showing charge
on the
ammeter last season. Now, the needle hardly moves although the voltage of the
batteries seems to be increasing. The meter has a 'reverse' switch, so I can
view
the charge used by lights, etc. That seems to be working. The only thing
left that
I can think of is the reversing switch, but that is in series with the
charging circuit, so
any open circuits would not allow the battery voltage to go up. Any ideas on
what
is going on here?

Sherwin D.

Usually when I find a battery that seems to charge to a higher than
normal voltage, and yet requires very little current to do it, the battery
is becoming sulphated and developing high internal series resistance.
This is sometimes evidenced by a battery which will run lights normally
and even for long periods of time, and yet will not crank over the engine.
And then the strange part is, even though it can't develope enough peak
energy to start your engine, it will appear fully charged about 5 minutes
after connecting it to your charger. Your battery seems to be acting this
way. Could you borrow a battery from someone, or perhaps from some other
piece of equipment around your home (tractor, mower, etc.) and see if
your system behaves more like you expect it to?

One other weird thing, a very dead battery that can barely light a lamp
will at first connection to a charger show a very high charge voltage
and draw almost no current, after about 1/2 hour the voltage will drop
somewhat and the current draw will go up (like when it goes to 6 or 8 amps
on a home charger with a green/yellow/red scale ammeter) then as you
approach full charge the voltage goes back up and the current comes down.