Weird battery issue

[AndyP]

I think your alternator is knackered and is not charging the battery properly, for reference these are the numbers off mine:-

Battery voltage, engine off : 12.82v
Battery voltage , engine running : 14.06v
Alternator voltage, engine running : 14.42v

[twoqu]

But you haven't actually bought a new battery have you? You have bought a battery that was rattling around in an RAC Van for god knows how long and then sat around in the back of Andy P's car. Thats why its not fully charged. If you purchase one from a battery distributor it would be fully charged.
The recondition is only for heavily discharged batteries to try and bring them back to life. Just use either of the regular modes, as too much voltage is just as bad as too little.
Its no good being arsey with people trying to help as it tends to discourage participation. If you want to be letdown at the most inconvenient time by a flat battery then do nothing.

[AndyP]

But you haven't actually bought a new battery have you? You have bought a battery that was rattling around in an RAC Van for god knows how long and then sat around in the back of Andy P's car. Thats why its not fully charged. If you purchase one from a battery distributor it would be fully charged.
The recondition is only for heavily discharged batteries to try and bring them back to life. Just use either of the regular modes, as too much voltage is just as bad as too little.
Its no good being arsey with people trying to help as it tends to discourage participation. If you want to be letdown at the most inconvenient time by a flat battery then do nothing.

Oi!! My car will have done nothing but good to that battery

[A80Avant]

But you haven't actually bought a new battery have you? You have bought a battery that was rattling around in an RAC Van for god knows how long and then sat around in the back of Andy P's car. Thats why its not fully charged. If you purchase one from a battery distributor it would be fully charged.
The recondition is only for heavily discharged batteries to try and bring them back to life. Just use either of the regular modes, as too much voltage is just as bad as too little.
Its no good being arsey with people trying to help as it tends to discourage participation. If you want to be letdown at the most inconvenient time by a flat battery then do nothing.

I'm not being arsey. I'm being logical. Have never encountered this problem before, have no clue of electrical gremlings so what may seem to you A to B in battery cars may be miles away for someone else. Before Googling into eternity I made this thread and get contradicting information. So have to eventually do the tests before blindly believing one or the other.

Please don't let the written language form seem that I'm being a wise ***.

[A80Avant]

I think your alternator is knackered and is not charging the battery properly, for reference these are the numbers off mine:-

Battery voltage, engine off : 12.82v
Battery voltage , engine running : 14.06v
Alternator voltage, engine running : 14.42v

Thanks Andy. That's does shed more light.

Now need to look for a good alternator choice for future replacement. As well as drive the car more often!


edit: It was the voltage regulator that we only replaced 4 years ago as it had mild tiredness, but the actual alternator was in good shape otherwise.

[AndyP]

Thanks Andy. That's does shed more light.

Now need to look for a good alternator choice for future replacement. As well as drive the car more often!

Might just want a new voltage regulator, I got mine from here

http://www.woodauto.com/default.aspx

About £15, dead easy to fit, well, if you havn't got a reverse inlet manifold

Try and have a look at the back of your alternator and make sure you have the 120a version.

[A80Avant]

is there an issue if i have the 90A and i fit a 120A one instead?

[AndyP]

No, my 3B had a 90a as std but I swapped it for 120a from an ABY.

[A80Avant]

ok i will give them a ring.

i would have thought that getting the undertray off and reaching the altenator from there to remove and refit would be accessible...

[caterpillar]

is there an issue if i have the 90A and i fit a 120A one instead? no prob with that; change the regulator in the back of the generator.... the bigger A doesnt help; if the regulator; (the unit between the alternator, and battery are good)

[A80Avant]

Possibly a silly question but since we established with a multimeter that the alternator is not producing enough voltage why the heck the cars voltage meter still shows 14V on idle? Does the regulator have anything to do with that?

[caterpillar]

alternator is not producing enough voltage why the heck the cars voltage meter still shows 14V on idle? its a cheap instrument... 14 v are too low....if you meshure the acid weight in the battery, you will figure why the battery are fullcharged, or not...low volt , below the 14,4v half charge battery..( 60Ah battey are only 30Ah) around 14,7 its perfekt....acidweight are about 1,28 (1,275)... bigger different than 0,2 in the cells= battery are defect...the low cell goes to produse current to be a user, and sucks the other calls dry...

[A80Avant]

alternator is not producing enough voltage why the heck the cars voltage meter still shows 14V on idle? its a cheap instrument... 14 v are too low....if you meshure the acid weight in the battery, you will figure why the battery are fullcharged, or not...low volt , below the 14,4v half charge battery..( 60Ah battey are only 30Ah) around 14,7 its perfekt....acidweight are about 1,28 (1,275)... bigger different than 0,2 in the cells= battery are defect...the low cell goes to produse current to be a user, and sucks the other calls dry...

Ok thanks. That's what I figured. Cheap instrument!

I have sourced an alternator and thanks to AndyP I may also get a regulator to rebuilt the current one. The link has all the reference numbers for the alternator parts and actual 120A units so hopefully I will have that replaced soon.

I suppose its normal after 4 years of use to have the voltage regulator fail then?

[caterpillar]

I suppose its normal after 4 years of use to have the voltage regulator fail then? @ no the regulator / where the coalbrush stays, may be ok for years, some alternators have deep tracks where the brush have digged out, som MAY the copper rings needed replaysment too( i have made the from some steel in 304.. they did last for 10 year...)

[Dybro]

Ok guys.. Now there has been posted a lot of different charge voltages.

Some of you might be aware of this already but some others is clearly not..
What you need to know is that the proper voltage changes when the temperature changes. The 2nd curve counting from the top is good for car batteries
Because the regulator has a fixed setting we need to select the best setting. I think that 14.4 volt will give you the best service life from the battery.
For those who live in northern scandinavia it might be good to switch to an other regulator in the winter period (e.g. when the temp is newer reaching 0 deg.C)
I have read that it is possible to buy programmable external voltage regulators, but that might be overkill


Also the open loop battery voltage (some hours after charging) is also affected by the temperature (excel file)

I hope this will help