Where was the alternator from as from what your saying I suspect that tbh?

Reason I ask about the light is if that dosen't work then you will have a no charge situation, something most woulden't think of but it's actually a critical part of the charging circuit, however revving hard enough can start the charge process.

Yes 11V= no charge that is the battery power your seeing, for it to charge you have to see 13V+ so as to overcome the internal resistance of the battery.

Martin