On Thursday, 9 March 2017 11:01:12 UTC, D.M. Procida wrote:
D.M. Procida wrote:

1. The car is used once or twice a week, mostly for short trips.

2. Nearly every time we use it, the battery is too dead to turn the
engine over and it needs to be charged. In fact it's so dead that even
trying will produce nothing but a click and drop the voltage across the
electrical system so low that it resets the clock.

3. After 20 minutes or so of charging, it'll start without difficulty
(it's only a 1.2l engine).

4. Alternatively, a quick push will do the trick.

5. If it has just recently been on a long drive (in the previous day or
so), or has been used once that day already, it will start without
problems, though.

6. More than once recently though I've stopped the car for a few moments
after driving several miles, and will find that it doesn't start and
needs a push to get going again.

7. It's getting worse.

8. The battery is fairly new.

Thanks for the many replies.

On the basis of advice, I disconnected the battery five days ago
(Sunday), charged it up, and left it disconnected. This morning
(Thursday) I reconnected it; the engine started immediately without
issue (and the same for multiple subsequent starts).

The battery reads about 12.3v while connected and the same disconnected.
At idle, it reads just about 14.3v.

I couldn't read anything between the battery earth and the chassis.

So it sounds to me that the battery is fine.

What do you suggest for the next step in the investigation?

Daniele

You don't need any high tech crap.
With the battery charged, disconnect it and then stroke the connector on the battery terminal.
Do it in dim light.
If current is flowing anywhere you'll see sparks. Even for a tiny current

If you don't this indicates the battery is not discharging into some component on the car there is some fault in the charging system.

Check for loose connections/broken wires appertaining to the alternator.
The tin wire goes to the ignition switch.
The thick wire goes to the battery.
There may be an external rectifier or it may be inside the alternator (More common these days.

If the alternator is working, you should see the highlights brighten when you rev the engine in the dark.

The alternator can be checked out on the bench but you need instruments.
The commonest fault is brushes worn/stuck.

http://www.wikihow.com/Rebuild-an-Alternator

On Thu, 9 Mar 2017 16:14:24 +0000, The Natural Philosopher wrote:

On the basis of advice, I disconnected the battery five days ago
(Sunday), charged it up, and left it disconnected. This morning
(Thursday) I reconnected it; the engine started immediately
without
issue (and the same for multiple subsequent starts).

What do you suggest for the next step in the investigation?

Well you have remade the connections.

It should be fine now as the lost likely explanation was a bad
connection.

Yep, leave it and use as normal for a week or so and see if the
problem returns.

--
Cheers
Dave.

"Dave Liquorice" wrote in message
idual.net...
On Thu, 9 Mar 2017 16:14:24 +0000, The Natural Philosopher wrote:

On the basis of advice, I disconnected the battery five days ago
(Sunday), charged it up, and left it disconnected. This morning
(Thursday) I reconnected it; the engine started immediately
without
issue (and the same for multiple subsequent starts).

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the battery
has been removed to recharge it and replaced to start the car. Of all the
suggestions that people have made over the week that this thread has been
running, that's one thing that you can discount: bad connections to battery.
Bad connections to alternator and to ground are a different matter.


It should be fine now as the lost likely explanation was a bad
connection.

Yep, leave it and use as normal for a week or so and see if the
problem returns.

On Tue, 14 Mar 2017 13:04:05 -0000, NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the
battery has been removed to recharge it and replaced to start the car.

I don't remember that being said. Charged yes but not removed other
than when being replace by a new one months to a year ago.

--
Cheers
Dave.

NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the battery
has been removed to recharge it and replaced to start the car

I don't remove it to charge it (or even disconnect it)! Should I?

Daniele

On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget to
much.

--
Cheers
Dave.

"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 13:04:05 -0000, NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the
battery has been removed to recharge it and replaced to start the car.

I don't remember that being said. Charged yes but not removed other
than when being replace by a new one months to a year ago.

You charged the battery while it was still connected to the car? I thought
that was usually likely to damage the electrics of most cars. It also means
that you have to get a mains supply to the car and leave it and the charger
unattended overnight, risky for theft if the car is kept on the drive.

The only time I've ever charged a battery, I've removed it, and taken it
into the garage to the charger and its mains plug. I thought that was the
only correct way to do it. Maybe I'm about to learn something :-)

"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget to
much.

If the battery has gone flat, especially if the starter motor has been
operated, the radio, clock etc will already have forgotten who they were,
what time it is etc.

In article
,
D.M. Procida writes
NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the battery
has been removed to recharge it and replaced to start the car

I don't remove it to charge it (or even disconnect it)! Should I?

Daniele
No
--
bert

"NY" wrote in message
o.uk...
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget to
much.

If the battery has gone flat, especially if the starter motor has been
operated, the radio, clock etc will already have forgotten who they were,
what time it is etc.

Normally not when it just sags badly when trying to start the car.

On 14/03/17 18:26, NY wrote:
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 13:04:05 -0000, NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the
battery has been removed to recharge it and replaced to start the car.

I don't remember that being said. Charged yes but not removed other
than when being replace by a new one months to a year ago.

You charged the battery while it was still connected to the car? I
thought that was usually likely to damage the electrics of most cars.
Bulll****.

The electrics is used to charge voltage - has to be.

Anyway 99% of the electrics is off when car ignition is off.

It
also means that you have to get a mains supply to the car and leave it
and the charger unattended overnight, risky for theft if the car is kept
on the drive.

The only time I've ever charged a battery, I've removed it, and taken it
into the garage to the charger and its mains plug. I thought that was
the only correct way to do it. Maybe I'm about to learn something :-)


--
If you tell a lie big enough and keep repeating it, people will
eventually come to believe it. The lie can be maintained only for such
time as the State can shield the people from the political, economic
and/or military consequences of the lie. It thus becomes vitally
important for the State to use all of its powers to repress dissent, for
the truth is the mortal enemy of the lie, and thus by extension, the
truth is the greatest enemy of the State.

Joseph Goebbels

On 14/03/17 18:27, NY wrote:
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget to
much.

If the battery has gone flat, especially if the starter motor has been
operated, the radio, clock etc will already have forgotten who they
were, what time it is etc.


Theres a lot of difference between unable to crank a starter and zero volts


--
The theory of Communism may be summed up in one sentence: Abolish all
private property.

Karl Marx

"Rod Speed" wrote in message
...


"NY" wrote in message
o.uk...
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget to
much.

If the battery has gone flat, especially if the starter motor has been
operated, the radio, clock etc will already have forgotten who they were,
what time it is etc.

Normally not when it just sags badly when trying to start the car.

With every car that I've had, if the battery won't power the starter (ie
even the courtesy light goes out when the starter is operated) the radio and
clock will reset.

I find that batteries will either give enough power to turn the engine over
or else will die totally under load, with no half-way house that causes a
gradual slowing of the starter over a few seconds. Usually there is no
warning. I get into the car and everything is normal, turn the key and all
the (interior) lights go out. I never start the car with the headlights or
heated rear window on, to give the battery every possible chance. Given that
my car is a diesel, which tend to need more power to overcome the higher
compression, I don't like to risk flattening the battery.

"The Natural Philosopher" wrote in message
news
On 14/03/17 18:27, NY wrote:
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 17:26:49 +0000, D.M. Procida wrote:

Surely the OP has remade the connections many times - every time
the
battery has been removed to recharge it and replaced to start the
car

I don't remove it to charge it (or even disconnect it)! Should I?

In theory yes, but who does?

Modern cars don't like having the battery removed, they forget too
much.

If the battery has gone flat, especially if the starter motor has been
operated, the radio, clock etc will already have forgotten who they
were, what time it is etc.


Theres a lot of difference between unable to crank a starter and zero
volts

Most radios/clocks seem to have a higher threshold that whatever terminal
voltage is available while starting, if the battery is almost flat. A flat
battery in my cars almost invariably means that the clock resets when I try
to start the engine; I think it's very rare that I *haven't* had to reset
the clock in that situation. That's in all the cars I've had which have had
a digital clock. Luckily most of my cars haven't had a coded radio - there
was just one where I had to find the code and the instructions on how to
enter it into the radio whenever the battery failed to operate the starter.

Next time I have a flat battery (which I hope will be never!) I'll have to
get my voltmeter out and see what the terminal voltage drops to when I start
the engine.

I know that the battery is *really* dead if the lights *don't go out,
because that means there is so little current available that it won't even
operate the relay to switch the heavy duty starter motor current

On 14/03/2017 18:26, NY wrote:

You charged the battery while it was still connected to the car? I
thought that was usually likely to damage the electrics of most cars. It
also means that you have to get a mains supply to the car and leave it
and the charger unattended overnight, risky for theft if the car is kept
on the drive.

Bonnet ajar, doors locked - why risky for theft? I might not do it onto
a street, but a drive in most places would be fine.

The only time I've ever charged a battery, I've removed it, and taken it
into the garage to the charger and its mains plug. I thought that was
the only correct way to do it. Maybe I'm about to learn something :-)

Removing the battery can be quite a PITA. Hefting that great lump around
etc. I never bother :-)

In article ,
NY wrote:
You charged the battery while it was still connected to the car? I
thought that was usually likely to damage the electrics of most cars.

If you can't charge the battery with it connected, how would you get away
with jump starting a car?

It also means that you have to get a mains supply to the car and leave
it and the charger unattended overnight, risky for theft if the car is
kept on the drive.

Hardly. Most cars have room for the charger under the bonnet. So just
route the mains lead out underneath the car and shut the bonnet. Might be
more tricky if the battery is in the boot, though.

The only time I've ever charged a battery, I've removed it, and taken it
into the garage to the charger and its mains plug. I thought that was
the only correct way to do it. Maybe I'm about to learn something :-)

It's a lot more work. ;-)

--
*Why isn't 11 pronounced onety one? *

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

On Tuesday, 14 March 2017 18:27:39 UTC, NY wrote:
"Dave Liquorice" wrote in message
idual.net...
On Tue, 14 Mar 2017 13:04:05 -0000, NY wrote:

What do you suggest for the next step in the investigation?

Well you have remade the connections.

Surely the OP has remade the connections many times - every time the
battery has been removed to recharge it and replaced to start the car.

I don't remember that being said. Charged yes but not removed other
than when being replace by a new one months to a year ago.

You charged the battery while it was still connected to the car? I thought
that was usually likely to damage the electrics of most cars. It also means
that you have to get a mains supply to the car and leave it and the charger
unattended overnight, risky for theft if the car is kept on the drive.

The only time I've ever charged a battery, I've removed it, and taken it
into the garage to the charger and its mains plug. I thought that was the
only correct way to do it. Maybe I'm about to learn something :-)

It was in days of yore.
Nowadays, as some one has said, cars "forget too much"
ie there are objects in the car need permanent power.

So, a widget exists which you connect up before removing the battery which maintains power. Usually plugs into the fag lighter.

Or you can just use another battery.

On 06/03/2017 08:57, Martin Brown wrote:

Several miles in winter when headlights tend to get used more may not be
enough to restore the energy taken from the battery to start the car.

Assuming there are no poor connections the charge rate won't vary much
with the load from lights etc. The alternator maintains the same voltage
irrespective of load. The alternator is more than capable of powering
the lights, heater motor, etc, and also charging the battery.

I drive a vehicle with digital ammeters and I observe this fact
frequently. I turn the headlights on, the voltage and charge rate dip
down momentarily, then they resume their previous position.

The idea that you can't charge the battery if you have the lights and
the heater blower on is a hangover from the days of dynamos. They had a
max output of, typically, 22A, and SFA on tick-over. A modern alternator
will produce 20A at tick-over and over 80A when the engine is running
normally. The alternator in my 20 year old motorhome will power a 24V
45A microwave and still charge the battery at 20A, power the headlights,
etc. (Yes, we use the micro when we're moving)

Bill

On 04/03/2017 12:02, NY wrote:

- Measure the charging voltage (voltmeter across the battery) when the
engine is idling and when it's revving at 2000 rpm. Certainly in the
latter case you should see around 14V - higher than the voltage without
the engine running.

Some Jap cars have a 15V alternator output. Doesn't seem to hurt the
battery and the charge rate is better. Probably blows bulbs though.

Bill

In article ,
Bill Wright wrote:
On 06/03/2017 08:57, Martin Brown wrote:

Several miles in winter when headlights tend to get used more may not be
enough to restore the energy taken from the battery to start the car.

Assuming there are no poor connections the charge rate won't vary much
with the load from lights etc. The alternator maintains the same voltage
irrespective of load. The alternator is more than capable of powering
the lights, heater motor, etc, and also charging the battery.

I drive a vehicle with digital ammeters and I observe this fact
frequently. I turn the headlights on, the voltage and charge rate dip
down momentarily, then they resume their previous position.

The idea that you can't charge the battery if you have the lights and
the heater blower on is a hangover from the days of dynamos. They had a
max output of, typically, 22A, and SFA on tick-over. A modern alternator
will produce 20A at tick-over and over 80A when the engine is running
normally. The alternator in my 20 year old motorhome will power a 24V
45A microwave and still charge the battery at 20A, power the headlights,
etc. (Yes, we use the micro when we're moving)

when I fitted an alternator to my Anglia, the extra load was too much for
the pressed steel pulley which broke, I had to buy a cast one - which Ford
were able to supply.

--
from KT24 in Surrey, England

In article ,
Bill Wright wrote:
The idea that you can't charge the battery if you have the lights and
the heater blower on is a hangover from the days of dynamos. They had a
max output of, typically, 22A, and SFA on tick-over. A modern alternator
will produce 20A at tick-over and over 80A when the engine is running
normally. The alternator in my 20 year old motorhome will power a 24V
45A microwave and still charge the battery at 20A, power the headlights,
etc. (Yes, we use the micro when we're moving)

I've a feeling many car makers now set the idle speed rather higher than
it need be purely to provide enough output from the alternator.

--
*If a turtle doesn't have a shell, is he homeless or naked?

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

On Thursday, 16 March 2017 00:45:14 UTC, Dave Plowman (News) wrote:
In article ,
Bill Wright wrote:
The idea that you can't charge the battery if you have the lights and
the heater blower on is a hangover from the days of dynamos. They had a
max output of, typically, 22A, and SFA on tick-over. A modern alternator
will produce 20A at tick-over and over 80A when the engine is running
normally. The alternator in my 20 year old motorhome will power a 24V
45A microwave and still charge the battery at 20A, power the headlights,
etc. (Yes, we use the micro when we're moving)

I've a feeling many car makers now set the idle speed rather higher than
it need be purely to provide enough output from the alternator.

Drivel.
The pulley on alternators is smaller than dynamos.
The alternator performs better because it runs faster.
It can run faster because there's no commutator.

On Wed, 15 Mar 2017 00:49:24 -0700 (PDT), harry wrote:

So, a widget exists which you connect up before removing the battery
which maintains power. Usually plugs into the fag lighter.

BTDTGTTS, small 12 V SLA battery bit of wire and ciggy plug. Just
make sure the ciggy socket is live and will remain so. I say "remain
so" as I have sneaky feeling that my car will switch it off like it
does the interior light, 10 to 20 mins after the start/stop button
has be pushed for "stop".

I haven't found the equivalent of the physical key ignition
"accesory" position and there are all manner of things making
whirring noises when you press start to enter "run" mode, not to
mention either side lights or the DLRs, so I suspect with engine
stopped and "ignition" on the battery drain is quite high.

--
Cheers
Dave.