m30 allternator on an m20?

[bimmer630]

Will an alternator from a 733 m30 fit on an m20?

[bimmer630]

I tried it. it fit. it does not charge though

[slammin.e28]

I tried it. it fit. it does not charge though

Why wouldn't it charge? If it's hooked up correctly and good, it should. All it needs to do is spin.