I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

TIA

DD

In article ,
D. Dalton wrote:

I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

A voltmeter connected across the battery can be useful for a quick check.
It should read approx 12.5v with the engine stopped, and around 14 with it
running, but no load extra loads like headlights.

However, a decent battery place should test it for you for free. Even
Halfords.

--
*It's a thankless job, but I've got a lot of Karma to burn off

Dave Plowman London SW
To e-mail, change noise into sound.

D. Dalton wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

TIA

DD
I am afraid sometimes that just happens - worst case seems to be car not
used for long periods..

D. Dalton wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

TIA

Check the battery voltage at the terminals using a DVM with the engine
running at a fast tickover. Anything over 13.7 volts means your charging
circuitry is probably okay. If it's lower, go for a run of about half an
hour in daylight and repeat the test.

Or take it to your local Kwikfit or other battery shop who offer a free
test, and ask them to put their tester on it.

--
Tciao for Now!

John.

D. Dalton wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

Do the lights brighten when you run the engine? Or to put it another way
if you turn the engine off do the headlights dim a bit? If so it
suggests the alternator is working.

Fanbelt OK?

Is the daily journey long enough to recharge after the starter motor has
been used?

When you fitted the new battery did you tighten the terminals enough?
Could be worth checking.

If the battery is one where you can add water, does it need water?

A £5 voltmeter would be good enough to check if the alternator is
providing a high enough voltage to charge the battery.

Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

Bill

Bill Wright wrote in
:


Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

Bill


Thanks to all for the helpful replies. I am cuurently charging the battery,
using my cheap battery charger. It only has one setting, and reduces its
charge as the battery charges up. Can anyone tell me how long I can leave
it thus charging? Is 15 hours too much?

Once the batter is charged, I will do some of the tests suggested
(tomorrow).

DD

In article ,
Bill Wright wrote:
Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

It's a long long time since I've seen 14.6v. Last probably with a dynamo.

--
*Never underestimate the power of stupid people in large groups.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
"D. Dalton" writes:
Bill Wright wrote in
:


Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

Bill


Thanks to all for the helpful replies. I am cuurently charging the battery,
using my cheap battery charger. It only has one setting, and reduces its
charge as the battery charges up. Can anyone tell me how long I can leave
it thus charging? Is 15 hours too much?

What's the charger's output in amps, and what's the capacity of the
battery in Amp Hours?

Once the batter is charged, I will do some of the tests suggested
(tomorrow).

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery? I would imagine
that would over charge it and lose the electrolyte, although probably
much faster than you are experiencing.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On 21/12/2011 19:27, Andrew Gabriel wrote:

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery?

That's the first time I've heard of a car battery being anything other
than lead-acid - except for electric vehicles of course, and historical
things like NiFe. Silver-calcium - sounds expensive - tell me more...

--
Andy

In message , Bill Wright
writes
D. Dalton wrote:
I installed a new battery in my car just two years ago. That seems a
bit recent for a battery to give out...
Is there an easy way to determine which is giving problems: the
battery or the charging system?

Do the lights brighten when you run the engine? Or to put it another
way if you turn the engine off do the headlights dim a bit? If so it
suggests the alternator is working.

Fanbelt OK?

Is the daily journey long enough to recharge after the starter motor
has been used?

When you fitted the new battery did you tighten the terminals enough?
Could be worth checking.

If the battery is one where you can add water, does it need water?

A £5 voltmeter would be good enough to check if the alternator is
providing a high enough voltage to charge the battery.

Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

Bill
Just to add to that, check earth connections from battery to body and
engine to body.
--
hugh

(Andrew Gabriel) wrote in
:

Can anyone tell me how
long I can leave it thus charging? Is 15 hours too much?

What's the charger's output in amps, and what's the capacity of the
battery in Amp Hours?


4 amp charger and 95Ah battery.

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery? I would imagine
that would over charge it and lose the electrolyte, although probably
much faster than you are experiencing.

Gosh - I don't know; the battery was chosen by a battery dealer who looked
up a battery that was supposed to suit my vehicle, but they may have got it
wrong.

DD

On 21/12/2011 19:45, Andy Wade wrote:
On 21/12/2011 19:27, Andrew Gabriel wrote:

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery?

That's the first time I've heard of a car battery being anything other
than lead-acid - except for electric vehicles of course, and historical
things like NiFe. Silver-calcium - sounds expensive - tell me more...

It's still lead-acid, but there's extra bits.

(Andrew Gabriel) wrote in
:


Can anyone tell me how
long I can leave it thus charging? Is 15 hours too much?

What's the charger's output in amps, and what's the capacity of the
battery in Amp Hours?

4 amp charger ; 95Ah battery

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery? I would imagine
that would over charge it and lose the electrolyte, although probably
much faster than you are experiencing.

I don't know. It was chosen by a battery dealer hundreds of miles from
here, while I was travelling once. He selected it from some computer
database as being suitable. That's all I know. The present battery is made
by CBX and I can't determine the model just now. It's a 700 amp 95 Ah. The
vehicle is a Mitsubishi Delica 1995 2.8TD auto 4x4 (Japanese grey import).

DD

"Clive George" wrote in message
o.uk...
On 21/12/2011 19:45, Andy Wade wrote:
On 21/12/2011 19:27, Andrew Gabriel wrote:

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery?

That's the first time I've heard of a car battery being anything other
than lead-acid - except for electric vehicles of course, and historical
things like NiFe. Silver-calcium - sounds expensive - tell me more...

It's still lead-acid, but there's extra bits.


There are glass mat batteries too, but I haven't looked at what's different
about them. They are fitted to stop/start cars.

On Dec 21, 7:56*pm, "AL_n" wrote:
(Andrew Gabriel) wrote :

Can anyone tell me how
long I can leave it thus charging? Is 15 hours too much?

What's the charger's output in amps, and what's the capacity of the
battery in Amp Hours?

4 amp charger and 95Ah battery.

24hr charge then.

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery? I would imagine
that would over charge it and lose the electrolyte, although probably
much faster than you are experiencing.

Gosh - I don't know; the battery was chosen by a battery dealer who looked
up a battery that was supposed to suit my vehicle, but they may have got it
wrong.

DD

Well, tell or show us exactly what it says on the battery, and what
type of battery your model should take, after googling for the info.
Charging voltage also matters on the car - and perhaps on your charger
too.


NT

In article ,
D. Dalton wrote:
(Andrew Gabriel) wrote in
:


Can anyone tell me how
long I can leave it thus charging? Is 15 hours too much?

What's the charger's output in amps, and what's the capacity of the
battery in Amp Hours?

4 amp charger ; 95Ah battery

15 hours at 4 amps = 60AH, so if the battery is 'flat' it sounds about
right.

Bear in mind that modern cars have a lot going on even when the ignition is
switched off and modern electrics can take a lot out of the battery. If you
do short journeys in winter, you probably don't replace the energy used
when starting. I left a car in an airport car park for two weeks and the
battery had almost flattened itself in that time.

--
From KT24

Using a RISC OS computer running v5.16

In article ,
Andy Wade writes:
On 21/12/2011 19:27, Andrew Gabriel wrote:

Have you by chance fitted an old style lead acid battery into a car
which is intended to take a silver calcium battery?

That's the first time I've heard of a car battery being anything other
than lead-acid - except for electric vehicles of course, and historical
things like NiFe. Silver-calcium - sounds expensive - tell me more...

Can be charged at a much higher voltage (I think up to somewhere
around 16V, but I haven't looked into the details). This has to
be done in a much more controlled way, and therefore it's done
when the engine management system is directly controlling the
alternator output regulation in conjunction with setting the
engine speed. One side effect is full alternator output at idle
engine speed, because the EMS will supply the additional fuel to
match the extra output it's telling the alternator to produce.
The EMS also knows which loads are on (lights, wipers, etc), and
uses this in calculating required alternator output. It also takes
into account engine compartment temperature, because the high
charging voltage is only used when the battery is cold. In the
original smart charging systems, you could simply unplug the
signal connection to the alternator and the whole system fell
back to conventional lead-acid alternator system, but I don't
know if that's still true today.

Ford have done this for a long time, even on the most basic models.
I don't know which other manufacturers use ilver calcium smart
charging.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In article , Zapp Brannigan
wrote:

"charles" wrote in message

Bear in mind that modern cars have a lot going on even when the
ignition is switched off and modern electrics can take a lot out of
the battery. If you do short journeys in winter, you probably don't
replace the energy used when starting. I left a car in an airport car
park for two weeks and the battery had almost flattened itself in that
time.

I *assume* my battery will be flat after 2 weeks in winter, and leave the
jump leads and a pair of gloves handy in the boot for return.
Borrowing a jump from another car is a simple 5 minute job if you have
the equipment, and much preferable to waiting an hour for the RAC or
airport to help you

I've kept jump leads in my car for years. They usually can be fitted in the
spare wheel compartment. Of course, modern cars make it difficult to get
at teh abtterry connections without tools - so you need those, too.

--
From KT24

Using a RISC OS computer running v5.16

On 21 Dec 2011 17:31:51 GMT, D. Dalton wrote:

I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

If it's 2 years old it is probably still under warranty. I had one die on
me over the intensely cold spell at the end of 2009-2010 when the car was
iced up for 3 weeks solid. The battery shop checked my alternator was
putting out the correct voltage and when they saw that it was, replaced the
battery without any further questions.

D. Dalton wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

Do the lights brighten when you run the engine? Or to put it another way
if you turn the engine off do the headlights dim a bit? If so it
suggests the alternator is working.

Fanbelt OK?

Is the daily journey long enough to recharge after the starter motor has
been used?

When you fitted the new battery did you tighten the terminals enough?
Could be worth checking.

If the battery is one where you can add water, does it need water?

A £5 voltmeter would be good enough to check if the alternator is
providing a high enough voltage to charge the battery.

Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

Bill

On Dec 21, 5:31*pm, "D. Dalton" wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...
Is there an easy way to determine which is giving problems: the battery or
the charging system?

Using a DVM on voltage range...
1 - Engine running at 2000rpm. Battery voltage should be 14.3V re
alternator voltage regulator.
2 - Engine off. Battery voltage should be 12.65-12.45V, 12.24V means
50% charge level & nearing end of life.

Many alarm systems & immobilisers fail progressively over years
drawing more current. This is particularly true of factory alarms
which interlink with the door locks, you get a drain of 180-420mA
which is far above the ideal limit of 30mA (0.03A).

Using a DVM on 2A current range (fuse protected)...
1 - Engine off. Remove negative battery terminal. Clamp one DVM lead
to the negative battery terminal. Touch the battery terminal to the
battery negative terminal. Press any keyfob to disable the alarm which
auto-arms on power up. Clamp the other DVM lead to the negative
battery terminal. Remove the battery terminal BUT keep one DVM lead
connected to it AND one DVM lead connected to the battery terminal.
This slightly long winded process is required to avoid the "alarm auto-
arm" and bonnet-open and ECU/Radio powerup initial current surge
blowing the 2A fuse.
2 - You can now read the car battery parasitic drain - which is
typically 30mA or less. If the figure is higher, such as 123mA that
will take most car batteries to 50% capacity within a weak, and in
very low temperatures starting may difficult or even impossible, and
over time the battery aging will result in "weak battery" at about
2yrs.

One unfortunate problem is the drain may be 30mA, but after some time
go higher. A logging DVM ammeter capability can be handy to spot this,
suddenly spiking up to 200mA after a while. Door interlock links are
notorious, it can be necessary to disconnect any link (usually a plug
into a box under the passenger footwell) between the door-lock module
and alarm module. The alarm & powerlock remain operational, but the
link is removed.

Some alarms on battery reconnect auto-powerlock the doors, flash
hazard lights & turn on interior lights so even the 10A DVM current
range will not be sufficient hence the need to do step #1 as above.
Otherwise you can fry a meter quickly. For this reason the OP may want
to pick up a cheap £5-10 DVM from HK-UK off Ebay. They are quite
adequate, just never use them with Mains because the Category rating
is usually low or rubbish (£5-10 meters can and do explode if they
carry a mains fault despite HRC fuses, posh ones just explode your
wallet).

If the battery is an all-black exide unit the 2009 & 2010 winters have
probably stuffed it, it was very brutal on car batteries. You can pick
up Bosch Silver (S3 S4 S5?) units on Ebay or online quite cheaply. The
generic car shop batteries are mean to last the warranty and a day. A
high current drain will kill any battery, as will a defective diode in
the alternator or defective alternator, likewise a courtesy door
switch in the glove box, boot, door, or moisture condensation causing
a low drain in same. Worth giving the door switches a good wiggle
every so often, even remove & electrical silicone grease.

For the most basic battery charger, time (hours) is capacity (Ah)
divided by charge current (Amps). So a 90Ah battery charged at say 4A
needs about a day on charge. You want to get up to about 75%. Of
course, the battery may be too damaged. Ctek XS4003 or MXS4.3 or
whatever the current model designation is a good smart charger with
LEDs to tell you what it is doing and hilariously when it is
blindingly obvious the battery is utterly stuffed (12.08V after a
charge, stinks of hydrogen sulphide and an on car voltage of 0.00V
when asked to light the door lights).

Beware shorting positive to body when working on the battery, things
will get hot & spark. Remove watches, watch spanners.

Oh, another cause - bad battery terminal & car-body ground corrosion.
A corroded battery negative wire & terminal will reduce charging over
time, even creating occasional no-start. The battery terminal clamps
with two pozi drive screws are crap, use a proper stud with crimped
lug and nut tightened down on it. Very good way of killing a
battery... every 1-2yrs and having a variable poor start based on
temperature & vibration.

On 22/12/2011 12:27 p.m., js.b1 wrote:

Using a DVM on voltage range...
1 - Engine running at 2000rpm. Battery voltage should be 14.3V re
alternator voltage regulator.
2 - Engine off. Battery voltage should be 12.65-12.45V, 12.24V means
50% charge level& nearing end of life.
....

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

In article ,
Gib Bogle wrote:
On 22/12/2011 12:27 p.m., js.b1 wrote:

Using a DVM on voltage range...
1 - Engine running at 2000rpm. Battery voltage should be 14.3V re
alternator voltage regulator.
2 - Engine off. Battery voltage should be 12.65-12.45V, 12.24V means
50% charge level& nearing end of life.
...

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Even the most crude charger will taper the charge rate down as the battery
reaches full charge. A recent half decent one will switch off when the
battery is fully charged. But they are tolerant devices, and few chargers
found in the home will do any harm by leaving on a few hours after the
battery is fully charged. So basically an overnight charge should be
enough to start a car even with a fairly low battery, but won't do any
harm to a near fully charged one.

Lidl and Aldi often have a good little charger on sale for about 13 quid.
Big enough to charge a battery overnight, but fully automatic and switches
off when it's charged.

--
*Time flies like an arrow. Fruit flies like a banana.*

Dave Plowman London SW
To e-mail, change noise into sound.

On 21/12/2011 21:12, Andrew Gabriel wrote:
In ,
Andy writes:
[...] Silver-calcium - sounds expensive - tell me more...

Can be charged at a much higher voltage (I think up to somewhere
around 16V, but I haven't looked into the details). This has to
be done in a much more controlled way, and therefore it's done
when the engine management system is directly controlling the
alternator output regulation [...]

Ah, OK, thanks. I mistakenly thought some completely different battery
chemistry was being referred to at first, rather than modified lead-acid.

--
Andy

Zapp Brannigan wrote:

I *assume* my battery will be flat after 2 weeks in winter, and leave
the jump leads and a pair of gloves handy in the boot for return.
Borrowing a jump from another car is a simple 5 minute job if you have
the equipment, and much preferable to waiting an hour for the RAC or
airport to help you

Ohh, you shouldn't do that to a battery. Normal lead-acids aren't
designed to be left in a deep discharged state. Get one of those little
photovoltaics and stand it in the car facing south.

Bill

In article ,
Bill Wright wrote:
Zapp Brannigan wrote:

I *assume* my battery will be flat after 2 weeks in winter, and leave
the jump leads and a pair of gloves handy in the boot for return.
Borrowing a jump from another car is a simple 5 minute job if you have
the equipment, and much preferable to waiting an hour for the RAC or
airport to help you

Ohh, you shouldn't do that to a battery. Normal lead-acids aren't
designed to be left in a deep discharged state. Get one of those little
photovoltaics and stand it in the car facing south.

Neighbour with a Porsche - obviously a great car since it hardly ever
moves - has one of these. AA were there the other day trying to start it.
Guess they failed as it was removed on a low loader.

Most standard cars will do at least 3 weeks without use. Many a great deal
more. If they have aftermarket alarms and ICE systems, etc, your guess is
as good as mine.

--
*Some days we are the flies; some days we are the windscreen.*

Dave Plowman London SW
To e-mail, change noise into sound.

On Thu, 22 Dec 2011 13:04:56 +1300, Gib Bogle
wrote:

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Do the calc first to give you an idea of how long max it should take.
Leaving it on charge for days on end with a crude basic charger is
what can stuff it.
Having said that, the basic crude traditional charger is still bloody
useful to pump some charge into a battery when the modern electronic
chargers will give up on it.

In article ,
writes:
On Thu, 22 Dec 2011 13:04:56 +1300, Gib Bogle
wrote:

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Do the calc first to give you an idea of how long max it should take.
Leaving it on charge for days on end with a crude basic charger is
what can stuff it.
Having said that, the basic crude traditional charger is still bloody
useful to pump some charge into a battery when the modern electronic
chargers will give up on it.

Yes. Someone mentioned the Aldi ones, and they are indeed excellent.

One fault I've found is that if the battery is very flat, the charger
will auto-detect it as a 6V battery, and think it's fully charged in
about 5 seconds when it gets to around 7V, and it's impossible to get
past that point. What I did was just connect up a low powered wall-
wart PSU to the battery for about a minute which got the battery up
to 8 or 9 volts, which is then correctly detected as a 12V battery
by the charger, and proper charging commences.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

In message ,
writes
On Thu, 22 Dec 2011 13:04:56 +1300, Gib Bogle
wrote:

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Do the calc first to give you an idea of how long max it should take.
Leaving it on charge for days on end with a crude basic charger is
what can stuff it.
Having said that, the basic crude traditional charger is still bloody
useful to pump some charge into a battery when the modern electronic
chargers will give up on it.
Plus a modern charger may well not charge an absolutely flat battery.
--
hugh

In article ,
Andrew Gabriel wrote:
Yes. Someone mentioned the Aldi ones, and they are indeed excellent.

One fault I've found is that if the battery is very flat, the charger
will auto-detect it as a 6V battery, and think it's fully charged in
about 5 seconds when it gets to around 7V, and it's impossible to get
past that point. What I did was just connect up a low powered wall-
wart PSU to the battery for about a minute which got the battery up
to 8 or 9 volts, which is then correctly detected as a 12V battery
by the charger, and proper charging commences.

Or if you have a jump start pack, connect that across the battery as well
as the charger for a while, then disconnect. The charger should then be
fine if the battery isn't knackered.

--
*One nice thing about egotists: they don't talk about other people.

Dave Plowman London SW
To e-mail, change noise into sound.

On 21/12/2011 18:43, Dave Plowman (News) wrote:
In ,
Bill wrote:
Voltage across battery with engine off, sidelights on: 12.5V approx.
Voltage across battery with engine on and at a fast tick over,
sidelights on: 14.6V approx.

It's a long long time since I've seen 14.6v. Last probably with a dynamo.


My 2003 Focus 1.6 with no load was 14.8v with low ambient temps.

David

On 23/12/2011 3:41 a.m., wrote:
On Thu, 22 Dec 2011 13:04:56 +1300, Gib
wrote:

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Do the calc first to give you an idea of how long max it should take.
Leaving it on charge for days on end with a crude basic charger is
what can stuff it.

Mine is a crude basic one, and I fear that I may have caused damage on
occasion.

On Wed, 21 Dec 2011 22:45:47 +0000, Bill Wright wrote:

When you fitted the new battery did you tighten the terminals enough?
Could be worth checking.

Along with a dob of vaseline to keep them corrosion free. Check the
earth bonding straps from the engine block to the chassis as well.

The OP doesn't say what the actual problem is but assuming poor
starting it doesn't take much resistance any where in the high
current starter circuit to make things "difficult".

--
Cheers
Dave.

On Thu, 22 Dec 2011 10:52:18 +0000 (GMT), Dave Plowman (News) wrote:

Most standard cars will do at least 3 weeks without use. Many a great
deal more.

Aye, most surprised when I need to move the other halfs car last
week. It hasn't moved or been started since the end of August when
she fell down the stairs and banged her shin. Lets say 4 months/18
weeks. Cleared the 5" of snow of it, opened the door (on the blipper
no problem), switched it on it all lit up brightly, turned the
starter. It was slightly reluctant for the first two compressions
then off it went. I was expecting it to be pretty much as dead as a
DoDo after that amount of time and below zero temps for a few days.
Suzuki SX4 1.6 diesel.

--
Cheers
Dave.

On Fri, 23 Dec 2011 09:57:53 +1300, Gib Bogle
wrote:

Mine is a crude basic one, and I fear that I may have caused damage on
occasion.

Well, if you know you're laying the battery up for a while, you can
still utilise a basic charger - just have it timed to come on for
30mins/day or for a longer period limit the charging current to half
an amp or so. I found a headlamp filament is a readily available
resistor.
I've been using both of these techniques for years before I bought
some Lidl chargers and the batteries survived well enough.

In article ,
Gib Bogle wrote:
On 23/12/2011 3:41 a.m., wrote:
On Thu, 22 Dec 2011 13:04:56 +1300, Gib
wrote:

Your post reminds me of something I've often wondered about when using a
battery charger. Is it possible to damage a battery by leaving it on
charge for too long? Should I always do the Ah calculation to determine
how long to give it?

Do the calc first to give you an idea of how long max it should take.
Leaving it on charge for days on end with a crude basic charger is
what can stuff it.

Mine is a crude basic one, and I fear that I may have caused damage on
occasion.

What is the quoted output in amps? But these basic units use a simple
series resistor to limit the output current to the maximum the charger can
supply, so will reduce the output as the battery charges.
So if the normal 5 amp or so unit, leaving it on for a few extra hours
won't have done any harm. Several days, possibly.

--
*A bicycle can't stand alone because it's two tyred.*

Dave Plowman London SW
To e-mail, change noise into sound.

On Dec 21, 5:31*pm, "D. Dalton" wrote:
I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

I presume you have sorted it by now, thanks for informing us BTW.

Someone mentioned checking the terminals for slack, nobody mentioned
checking them for salt.

If you have corrosion on the terminals, take them off sand them clean
wax them over and refit after a recharge.

A jump start and a brief run out in low gear should sort it. It should
get a bang charge from the system enough to get it going after that.

If you ever find yourself stranded in the middle of nowhere with
salted battery terminals, a flush with lemonade or urine or whatever
you can find, will wash it off. It might then just start itself.

Salted over terminals will insulate the battery and stop it
discharging; that is to say: stop it working. Cleaning them usually
sorts it.

I don't have to remind you, do I, to take the battery out when you get
home after ****ing on it?

Or why?

On Dec 24, 10:50*pm, Weatherlawyer wrote:
On Dec 21, 5:31*pm, "D. Dalton" wrote:

I installed a new battery in my car just two years ago. That seems a bit
recent for a battery to give out...

Is there an easy way to determine which is giving problems: the battery or
the charging system?

I presume you have sorted it by now, thanks for informing us BTW.

Someone mentioned checking the terminals for slack, nobody mentioned
checking them for salt.

If you have corrosion on the terminals, take them off sand them clean
wax them over and refit after a recharge.

A jump start and a brief run out in low gear should sort it. It should
get a bang charge from the system enough to get it going after that.

If you ever find yourself stranded in the middle of nowhere with
salted battery terminals, a flush with lemonade or urine or whatever
you can find, will wash it off. It might then just start itself.

Salted over terminals will insulate the battery and stop it
discharging; that is to say: stop it working. Cleaning them usually
sorts it.

I don't have to remind you, do I, to take the battery out when you get
home after ****ing on it?

Or why?

Easier to just wipe the crystals off with a file.

With no feed back from the OP on terminal voltage under charge, all we
can do is guess the cause.


NT