Battery Amps Question

[troy]

How many amps should your battery show on the gauge with just the key turned on and motor not running.
Went to get the boat ready and motor would not lift so i thought the battery was flat.
Charge battery for 13 hours with a 2.5 amp charger and motor still would not lift and turned out to be a fault in the power trim.
Question is the charger lights are a bit faulty so do not know if battery is fully charged as only reading 11 amps on gauge with motor not running.
Is this normal and how long should you charge a battery for on a small charger.
Do not want to risk do ing damage by over charging.
Thanks
Troy

[troy]

Better explain properly i did not want to start the motor as fuel is a bit old and was going to drain the tank.
I know amps will be higher with motor running but not sure what they should be with just the key turned on so does it need more charging.
Thanks
Troy

[Steboe]

A 2.5amp battery charger won't overcharge a boat battery

Regards, Ken

[black runner]

Are you talking about a volt meter or ammeter reading? They are two completely different beasts.

I suspect you are talking volts and the gauge is showing 11 volts fully charged? If so you have a crook battery or something is drawing excessive current when the ignition switch is in the "on" position. Disconnect the battery and test with a multimeter and hydrometer.

Check terminal voltage which should be about 12.7 volts. This indicates a fully charged battery and drops to 12.4v at 75%, 12.2v at 50%, 12.0 at 25% and 11.9volts discharged.

Also check specific gravity (that is if your battery isn't sealed) using the hydrometer 1.265 being fully charged down to 1.120 discharged at 11.9 volts. Readings between cells shouldn't vary by more than .05 and if so can indicate a dicky cell.

With everything connected and motor running you should be seeing 13.8 - 14.2volts at the terminal if your alternator is working (However not sure of the output of your motor's alternator).


Cheers

[troy]

Are you talking about a volt meter or ammeter reading? They are two completely different beasts.

I suspect you are talking volts and the gauge is showing 11 volts fully charged? If so you have a crook battery or something is drawing excessive current when the ignition switch is in the "on" position. Disconnect the battery and test with a multimeter and hydrometer.

Check terminal voltage which should be about 12.7 volts. This indicates a fully charged battery and drops to 12.4v at 75%, 12.2v at 50%, 12.0 at 25% and 11.9volts discharged.

Also check specific gravity (that is if your battery isn't sealed) using the hydrometer 1.265 being fully charged down to 1.120 discharged at 11.9 volts. Readings between cells shouldn't vary by more than .05 and if so can indicate a dicky cell.

With everything connected and motor running you should be seeing 13.8 - 14.2volts at the terminal if your alternator is working (However not sure of the output of your motor's alternator).


Cheers

Hi the gauge is showing 12 volts without motor running.
Do you think it needs more charging or battery problems.
Thanks
Troy

[troy]

Hi the gauge is showing 12 volts without motor running.
Do you think it needs more charging or battery problems.
Thanks
Troy

The motor is a 150 e teck and i am getting the reading just of the gauge on the panel.
Thanks Troy

[TheRealAndy]

A 2.5amp battery charger won't overcharge a boat battery

Regards, Ken

That depends on the charger. one of those $15 buck cheapies from super cheap will.

[Ready Jet Go]

If you charged your battery for 13 hrs it should be charged up enough to start motor make sure water level is correct ( use distilled). 2 common reasons a battery wont work is sulphated plates ( reduces capacity ) occurs if you leave battery for a long time without use as whenever battery is below 12.6v it will be having a chemical reaction trying to acheive 12.6v ( the further below 12v the more sulphate on plates -irreversable). if you crank engine without starting voltage will rapidly drop below 11v if plates are sulphated. Reason 2 is a dead cell where after you charge battery then disconnect battery charger and measure voltage after 1hr you will get less than 12V ( batteries can also short internally and then flatten themselves)

my guess is 11v after charging means dead cell.( crook cell will usually bubble a lot more than the others after being on charge for a while)
volt meter on boat should always show >=12v unless something is on
if its a float charger leave battery on charge 24/7
if its not a float charger switch (2.5 amp) charger on every fortnight for 3-4 hrs unless you use boat

Dean ( Marine electrician )

[troy]

I gave it another 12 hours on the charger and now showing 13 volts on gauge with motor not running.
Is this okay and no dead cell.
Thanks
Troy

[Blackened]

G'day

I'd be looking elsewhere troy.

All switches turned on that are meant to be? no loose connections at the battery? no corrosion?

Dave

[troy]

G'day

I'd be looking elsewhere troy.

All switches turned on that are meant to be? no loose connections at the battery? no corrosion?

Dave

Dave the motor had not been run for a fair while so i was thinking that when i charged it i did not have it on long enough.
With another 12 hours of charging it came up to 13 volts.
Do you think i still have a problem.
Thanks
Troy

[Blackened]

G'day

Is everything else like bilge pump, lights, trim and tilt, deck wash, sounder/gps working?

Dave

[troy]

Yes Dave everything is all working.
Thanks
Troy

[troy]

I think the battery is faulty as i just started the motor and upon starting the battery dropped back to 6 volts and then picked up tp 14 volts while running.
Tried again and same thing.
Thanks
Troy

[Blackened]

G'day

Have you got a battery you can test with to make sure the battery is a dud? Maybe something oiut of a 4x4?

Dave