Found a 90amp alternator at last for my mk2 but...

[j_s]

Been offered a 90amp alternator but the guy selling it to me has said the following:

"When i had my Golf the alternator died so went to a place that reconditioned them and paid extra to have the uprated version. Blew engine up about five thousand mile later and stripped car, so been in a cupboard in garage ever since. Will check to make sure its ok.
One thing though, it will put your battery light on, on the dash, because the car will think its overcharging (because its a bigger output alternator). Dont know if you have to change a relay or what???

Just been and had a look in garage. Spins nice and freely, no play in bearings. Its a Bosch one too. Took a few photos with camera. Tell me your e-mail address and i can send you photos.
Might be worth posting asking about will an uprated alt put the battery light on dash"

Anyone know if it's simply a change of relay somewhere or do I need to do something else?

Cheers

[Mirage-]

I had an uprated re-conditioned 90amp alternator running on my last mk2 8v Gti, no warning light.

AFAIK the warning light is that the alternator is NOT charging, not that it's over-charging.

[monzablue16v]

I have a 90 amp alternator on my 16v and my battery light only comes on when there is no or a lack of charge to the battery. They can be reconditioned for about £50-60 as I had mine done.

[Bazzer]

IIRC there's a single wire you need to connect that goes to a warning light - might be that this has been left off (or removed) on this alternator.

[j_s]

Thanks guys as a precaution i've now sourced another from someone on clubgti 

[Dizzie]

a 90A alternator doesn't charge at a higher voltage lol
it just puts more amps in during it's charging to cope with more drain from large ICE systems, etc.
God my light would never go out with the 120A alternator I have on the mk2.

[monzablue16v]

Yeah it's the blue wire could be the brushes or could need a rebuild good idea getting a different one, remember blue wire

[j_s]

It's ok I picked up another one from someone else 

Running nicely now, and whoever says they get their lights dimming with a nice stereo install needs to sort their earths, power cables and a 90a alt, oh and a big Varta 75a battery   
My lights don't even twitch