Yesterday my alternator started rumbling and whirring. It was almost louder than the engine. The car wouldn't tick over very well and the battery light was on when driving.

Me thinks my alternator has shot it's bolt. I have been quoted £330 for a new one fitted all in from my local dealer. A quick look around the net shows the part is over £200 new. :o

Yesterday my alternator started rumbling and whirring. It was almost louder than the engine. The car wouldn't tick over very well and the battery light was on when driving.

Me thinks my alternator has shot it's bolt. I have been quoted £330 for a new one fitted all in from my local dealer. A quick look around the net shows the part is over £200 new. :o

Sounds likely, but how sure are you it was the alternator making the noise? sure it wasnt just a shot pulley?

Would a shot pulley cause the battery light to come on?

If it is the alternator, go into your local motorfactors and ask if they do them on an exchange system. Take yours off, take it in, give them yours and take a new one away.

Should be easy enough to change or is yours run by cambelt?

my alternator decided to go on my ST, if your battery light is on i wouldn't advise driving it anywhere as i was driving to work everything electronic practically went, ABS, Powered Steering, Radio, Lights, ESP not much fun when on a dual carriage way

Would a shot pulley cause the battery light to come on?

Shot pulley could (depending which one is shot!) because if its not rotating properly then it wont charge up. If your handy with a multimeter, you could take a look at the different contact points around the electrical system. I believe JohnH had a thread were he did alsorts of diagnostics, so I suppose if you ask him about it, he may be able to offer some advice on that.

hey, i heard my name from afar lol

yeah i would dust of the multimeter and do a fair few checks on your alternator and battery etc before wasting money like i did.

basically check the battery voltage with engine off. should be 12.5v (could be lower due to not enough charge)

check the voltage from the alternator to the battery, should be 14v. any lower say 11 - 13v. (get the smart charge looked at - can give more details if requested)

but if noise is definately coming from the alternator, sounds knackered like. check the condition of the belt also.

oh if you have a 105a alternator, i have a fully serviceable one for sale.

which reminds me never never never never turn your multimeter to read amps on a car...it hurts and you stick to the multimeter!

hey, i heard my name from afar lol

Only ever good things ;)

which reminds me never never never never turn your multimeter to read amps on a car...it hurts and you stick to the multimeter!

...

Lesson learned there JohnH!

I will remember not to try melting my multimeter. It's up there with the old don't lay the spanner accross the terminals trick...

Depends who your advising ;) I have asked a mechanic if he did that, he said yes what do you take me for... thought about it, then replied "no, that would be silly of me"... - So would saying yes before you have thought about it!

Alternator was buggered. New one fitted and car running well again.