<VV> Boiling Battery

[Ken Lundy]

After running my 64 convertible this morning, I noticed the battery fluid
was boiling over.
I measured the voltage at the battery terminals and got 16.9 volts.
I then tapped on the voltage regulator with a screwdriver handle and the
voltage dropped to 14.6.
Measured again about 10 minutes later and got 12.8.
Should I replace the regulator? Is there anything else that might be causing
this voltage fluctuation?

Regards,
Ken Lundy
NJ
64 Monza Convertible