Join Date: Aug 2009
Location: Sudbury, Ontario, Canada
It might just be a one-off issue. Sounds like the voltage regulator (probably integral with the alternator) was stuck. It normally switches on and off to top up the battery, as demand dictates.
If it stayed in 'off' mode, the car would be running on a slowly discharging battery. The sudden demand of starting the car may have 'woken up' the regulator.
If you're planning to keep the car a long time, put the Volvo part in. If not, name-brand, aftermarket would be fine.
64 Saab 96 Monte Carlo 850 clone, 73 1800ES, 74 Land Rover Series III, 80 Mini 1380, 04 Jeep GC Overland & 2010 Nitro