Potential Battery / Alternator Woes

[jtypecav]

Had noticed charge was getting lower (display was dimming more often etc..) then one day out to the car and it wouldn't crank. Battery was GM and about 3 years old. So I thought.. aah OK it's end of life. Tested the setup, found that it wasn't charging at all. So I popped a brand spanking alternator on there and everythign was good again - or so it seemed. The battery stopped holding charge later on (a few months ago) so I replaced it. But now I'm not so sure there isn't another gremlin in there.

The other day I serviced and checked the battery health. It seemed OK and whilst running was a healthy 13-14v on voltmeter / software tester. However, I could have sworn the display was dimmer again today - so tested it again - and it seems the average battery charge level was 12.0 to 12.6 today throughout. Definitively on the drop again.

In the past few years it's had two alternators and two batteries, really hoping there is a well known issue that someone can point me to here!

Any ideas?

[freecall666]

looks like you are getting a short some were in the charging systerm,
may just be intermitant, do you get light flicker at times, or do you get dim battery light on in the dark.

[jtypecav]

Thanks freecall, that's the strange bit. No battery illumination at all. Although at one point full beam light did illuminate but that was a separate issue with the lighting. Where is the first place to look or is 12.6 acceptable?!

[Andy H]

If you haven't already done so have a read and work your way through this excellent maintenance guide Battery, Charging and Starting Diagnosis

The issues that crop up repeatedly on Omegas are
- Disintegration of the crimped connections on the big leads to the battery (& earth strap).
- Corrosion/failure of the voltage regulator in the alternator
- Leaking batteries in the Power Sounder causing short circuit (& possible fire under the bonnet).

[freecall666]

do you have a towbar on mig the twin type?

[jtypecav]

Thanks Andy I'll check this out.

Freecall - yes there is a twin electrics towbar?!

[tidla]

If you haven't already done so have a read and work your way through this excellent maintenance guide Battery, Charging and Starting Diagnosis

The issues that crop up repeatedly on Omegas are
- Disintegration of the crimped connections on the big leads to the battery (& earth strap).
- Corrosion/failure of the voltage regulator in the alternator
- Leaking batteries in the Power Sounder causing short circuit (& possible fire under the bonnet).

my money is on this.

read the guides as suggested.
If you handy with a multimeter, a quick check is to start the car. turn on electrical loads and check for voltage drop, one probe on the negative terminal the other on the engine block. reading should be 0v. Any reading shows resistance in the connectors/cable.
Positive cable can be checked the same way.

[freecall666]

Thanks Andy I'll check this out.

Freecall - yes there is a twin electrics towbar?!

check the relay form the 12v plug for water getting in may be shorting out. and the wiring aswell in the boot.