I've been working on this one Optima for a couple days now. It was getting a bit warm during charging.
The Schumacher charger never did reach 10 amps charging, this is with a another good battery in parallel.
It went from about 4 amps to 7 amps. This evening when I unhooked everything, the Optima read 10 volts.
I'm going to check voltage in the morning to see if it drops. The charger was getting pretty warm too.
I'm going to keep going to see if I can get the Optima up to 12.7 volts. I don't want to keep the charger on
in the garage overnight unattended, for safety. The system does appear to be working though, albeit slow.