Morris Minor Owners Club

The only way to find out whether your battery is charging or discharging is with an ammeter.

cured with a 'known to be good' battery off a spare car, and the extra cable is doing the job of keeping the battery topped up and coping with the draw of the lights better than it used to.

Extra cable ??

Hello Chris,

when you first switch on you will get a voltage reading, which is battery voltage. As mentioned these car gauges are not necessarily accurate so just use it to compare. If your engine is then started, you should see the meter climb by about 2 volts, some are heavily damped so slow to react others are almost instantaneous. When you switch off the volts will drop, and in the instance you say when the engine stalled should just drop back to your original battery voltage.

Don't think of the alternator and the battery as being seperate, they are all of the one system, if your alternator voltage is higher than the battery voltage, the battery will charge, despite what other loads are switched on, the power doesn't decide to go to one and not the other.

The crux is your voltmeter, it should be higher when running than when you first switch on, if it doesn't then there is a problem that wants correcting.

Alec

Most of these 'voltmeters' are hot-wire ammeters - and so they take quite a while to climb and settle at the correct reading.........