I purchased a battery 4 weeks ago and have had trouble starting the car. I think it is the starter, however, I have had the battery on the charger for 3+ days and it is reading 13.1 volts open circuit. I seem to remember a new battery should be at 13.7V and that by the time it is at 12.0 it is time for a new one.
When connected to the car it is reading 12.8 volts.
Should a new battery be well above 13.1 volts (i.e. 13.7)?