Alternator voltage

[The devil]

Hi guys.

Having put a multimeter on the battery I am getting about 15.2 volts and sometimes rising to 16volts.

Would this be the regulator? if so are they normally part of an alternator or can they be changed as a part of it. the alternator is a ford part even though it is on a Noble

[Justin S]

Way too high, should be about 13.6v ish, depending on battery condition. The diode pack is in the back of the alternator. Some are replaceable. Best to get it out and apart to see if the parts are available. Is it a specific or just a Mondeo alternator? There are plenty of repair shops around who can repair the diodes easily, have a look in Yell or similar.

[The devil]

Many thanks, your a gent

[Justin S]

Here's a bit of info
http://www.familycar.com/classroom/charging.htm

[The devil]

I took the step of replaceing the alternator today and now the voltage is even higher 15.5 volts.
Bugger
Anyone any ideas at all

[stevieturbo]

buy a new voltmeter ?

[perdu]

stevieturbo said:

buy a new voltmeter ?

dont run the engine for an hour or so

turn on the headlights for a short time

turn them off

test the battery standing voltage

It should be around 12.8v (ish)

if the meter reads much more than that

what Stevie says...buy a new meter

The most a battery should register will be about 13.5v when static and that is quite unlikely.

[Pumaracing]

Why did you decide to test the charging voltage? What electrical problems if any are manifesting? This might help us to identify your problem.

[bdx]

Has to be your meter.
An alternator charging will read 14.4V

High water usage is a good indicator of a high charging voltage.

Edited by bdx on Wednesday 2nd June 08:36

[The devil]

Thanks for the replies guys.
The reason for starting testing was that the amplifier I have on the stereo kept cutting out and the circuit protection light kept coming on for the voltage.
I have tested it with 3 voltage meters now and 2 of them say about 15.4 volts, the other says 15 ish volts
I will try testing just the battery though

[Pumaracing]

The voltage is a tad high but not grievously so. Normally you'd expect an alternator to put out between 13.8 and 15.1 volts depending on battery type and charging circuit design.

Lead/calcium batteries require higher charging voltages than other types with up to 15.6 volts being claimed as either possible or even advisable.

You may have a defective battery or the wrong battery type for the charging circuit. You might want to think back if the OE battery has been changed at some time.

My 9 year old Ford Focus lead/calcium battery which stubbornly refuses to die is as happy as Larry with 15 volts plus when I recharge it and in fact achieved a higher rest voltage after I'd boiled the arse off it with 15v plus for a week after forgetting I'd left it on charge than at any time previously.

It only gets used once a month or so, has been left to run flat on numerous occasions, gets charged at whatever my antiquated charger throws at it and still soldiers on. I'm beginning to think the battery might actually outlast the car.

[finlo]

Ford charging systems when used with a calcium battery will charge at upto 18V depending on the air intake temp, a quick google of Ford "smartcharge" will give you plenty of info HTH.