battery charging problem

Hi All

I need some help with my series III SWB landy. The battery is not charging correctly. I initially thought it was the alternator because of the way it died.

I lost main beam first, then indicators, then main lights, side lights, eventually 5 miles from home a dead engine ---

I have replaced the alternator today for a brand new one, when the engine is running my multi reader is reading 13 - 14v on the 3 pin connector that is on the back.

With the old battery in, I went for a drive to try and give it a little charge, not only did the battery not charge, I lost brake and indicator lights also...

I have a new battery to install, however I would like to sort the charging problem out first... I don't want two flat batteries !

Can anybody point me in the right direction on what to do next? Have I missed something obvious?

Cheers

Craig B

does your SIII have a separate voltage regulator?
if so, it sounds as though it is goosed.

treworgey,

Firstly thanks for you quick reply..

What does a voltage regulator look like, and where is it usually on a Series III ?

I think my landy was originally a Petrol model that has had the Montego Turbo conversion.

The brand new alternator was a standard 3 pin one as found on a montego and serveral other cars, I had to transfer the fan and pully off the front and a little black lead and box on the back.

hmm, the separate reegulator was probably done away with at the time of conversion then - montego regulator is built in to the alt I believe.
it would be a black box mounted on the bulkhead in the injun bay. it would have 2 thick brown wires going in/out and one thin one I would guess.

sounds like you've got a wiring fault somewhere in the charging system, with an intermittent short or low impedance to earth. Try tracing the thick wire from your alt to your battery, looking for chafing or damage or dodgy connections.
alternatively, your current battery could be seriously sulphated and actually taking all the output from the alt and not charging at all - just getting hot.

3 leads comming from back of alt, two thick ones and a thin one.

the two thick ones both look like they go to the positive side of the battery.
(two thick wires at bottom of battery picture)

the thin one disappears into the bulkhead..

some wires from battery go into a black bosch box --
is this a voltage regulator ?

firstly get yourself a 240v car battery charger and put one of the batteries on it

if your getting 13-14 volts across the battery when it's running it doesnt sound like the alternator is the issue - as you would expect with a new one

it's much more likely to be a loose earth, seeing as so many circuits now dont work i would look at the main earth leg coming off the battery and work away from there

cssbutler said:

some wires from battery go into a black bosch box --
is this a voltage regulator ?

Click to expand...

your alternator almost certainly has the regulator built in, that bosch box isnt a standard part and can be ignored for now - unless someone has bodged the electrics up using bits

cssbutler said:

some wires from battery go into a black bosch box --
is this a voltage regulator ?

Click to expand...

... and I thought Lucas was the prince of darkness...

1st mesure the voltage across the bat with the engine off.
2nd start engine and measure across the bat again

The second reading should be 1v to 2v higher that the first.

The two large wires coming out of the alternator are to carry the charging current, the other smaller wire is the exciter wire/ warning light wire.
This wire should trace to the warning light on the dash the other side of which is fed by the ign on position. On landrovers this is usually brown/yellow from alt to ign warn light .
Most alternators will not charge a dead flat battery, unlike the old type dynamo.
If you lost brake and indicator lights you may have a fuse box problem as they are both fed from the ign on circuit, the reason you lost the other lights previous was the battery was discharging , no charge from alt.
This would progress untill there was insufficient current to feed the coil, turning all lights etc off would have extended the time the engine would have run. HTSH

The fact that he can start the engine off the battery tells us the earthing between engine and battery is good.

One has to start thinking about a disintegrating fuse block somewhere, when one considers the list of things that are failing like that, but a series of bad earths, or a really dodgy light switch could screw it up too.

CharlesY

Hi CharlesY et al

Thanks for all your replies..

My old battery is drained, when I try and start it I just get some loud clicks from the starter, not enough power to turn it over. If I jump the car using a jump start battery pack the engine kicks in and runs.. However if I take it out for a drive I lose indicators and brake lights.

I do have a new battery but would like to sort the charging problem out first.

When I get back home from contract (this weekend or next) I am going to check all the earthing points and possibly add another earth direct to the engine/alternator.

I am getting plenty of juice from the new alternator, but I fear I am not getting it across the battery.

when the engine is going the charge light is off.

that doesnt mean the battery is receiving a charge - measure the voltage across the battery when the engine is running

and then start the hunt for dodgy connections

Have you tried charging the old battery over night from the mains and then checked to see if its holding its charge and what the voltage is with engine running. As said above. An alternator will not charge a dead battery

I had this same problem! In the end, after replacing both alternator and battery, i removed/cleaned existing battery earths, and also added a couple more!

Plus, i made a new alternator lead (from old jump wire) that goes straight from alternator to battery. Now its perfect

Most charging faults are Earth related

Hi Ian3 et al

I am back on the ferry on friday night, so will be working on the landy all sat and sun to try and fix this.

Thankyou for all the quality advice and I will keep you posted !!

Cheers
Craig B

OK, two days of tinkering later and I have made a little progress.
Voltage across the battery with engine off = 12.5V
Voltage with engine on, glow plugs on = 11.5V
glow plugs off = 12.7V

here something interesting happens....
If I leave it idling for 5-10 mins voltage creeps upto 13.6V, however if I throttle up, instant drop back to around 12.5V

Drops down to 11.5V when I put lights on.

I have so far;
-rewired alternator to + battery,
-wired a new earth strap - to engine,
-rewired charge light wire
-cleaned up all terminals and connections with wire brush

Is it possible that my brand new out of the box alternator is broke? Or has anybody got any other ideas?

Cheers

Craig B

That sounds like it's doing what it's supposed to do. when you switch the lights on and get the voltage drop does it stabilise and climb back up to 12.5/13.5 Volt?

cssbutler said:

OK, two days of tinkering later and I have made a little progress.
Voltage across the battery with engine off = 12.5V
Voltage with engine on, glow plugs on = 11.5V
glow plugs off = 12.7V

here something interesting happens....
If I leave it idling for 5-10 mins voltage creeps upto 13.6V, however if I throttle up, instant drop back to around 12.5V

Drops down to 11.5V when I put lights on.

I have so far;
-rewired alternator to + battery,
-wired a new earth strap - to engine,
-rewired charge light wire
-cleaned up all terminals and connections with wire brush

Is it possible that my brand new out of the box alternator is broke? Or has anybody got any other ideas?

Cheers

Craig B

Click to expand...

wont b the first time. u should have a continuous 13.5 to 13.6 v at the battery with the engine running....could b a ferked v-regulator