Mk3 Astra, 12v on tickover

[teamster1975]

Weird one this, I was stranded in my mates Astra last week and had to change the battery and the alternator belt.
Tuns out the battery is fine having had it on the optimate over the weekend.
However; I stuck a multimeter across the battery on tickover and it only read 12.2V.
I balanced the meter so I could read it from inside the car and as soon as you hit above say 1800 revs it jumps to 14V.

So basically it was my own fault leaving the car running to defrost on Friday morning because it wasn't taking juice from the alternator!

Any ideas chaps apart from not being a lazy b@stard and scraping the car?

[steve_earwig]

Weird one this, I was stranded in my mates Astra last week and had to change the battery and the alternator belt.
Tuns out the battery is fine having had it on the optimate over the weekend.
However; I stuck a multimeter across the battery on tickover and it only read 12.2V.
I balanced the meter so I could read it from inside the car and as soon as you hit above say 1800 revs it jumps to 14V.

So basically it was my own fault leaving the car running to defrost on Friday morning because it wasn't taking juice from the alternator!

Any ideas chaps apart from not being a lazy b@stard and scraping the car?

Give it to him back and tell him the alternator's shagged? Sounds like the regulator and I don't think you can get them seperately now.

[teamster1975]

Don't worry, I haven't put any money into it, just did the mucky work changing the bits over!
(Especially considering the sump is weeping and there was congealed black shyte all around the general vicinity which even swarfega wouldn't get off my hands )
He's done me some big favours so I owed him one
Thanks for the advice, I'll trundle down the breakers I think!

[turbolag]

Alternator old chap - a very common MKIII (and the mechanically similar I & II) problem. Tell him to get it fixed before the battery dies from the strain, and tell him to expect the new one not to last beyond 3 or 4 years.