1937 magnetic solenoid clicking

[ron37ford]

I have a 1937 Ford Tudor.
The previous owner put a 12 volt battery to the solenoid and to the starter.
The 6 volt runs everything else.
This has happened before, but went away.
When starting, the solenoid just clicks and doesn't turn over.
The battery is fully charged, actually I overcharged it.
I tried to jump the solenoid to see if I could turn it over, but must be doing something wrong.
Is the clicking problem just replacing the solenoid.

Thanks,