On a previous catamaran
, I fitted a 200 A alternator to each engine
. The alternator was driven with a second drive pulley, a duel belt system using "high power" belts by various manufacturers.
They all failed after about 200 hours. I think the alternator was demanding demanding more power than they could deliver - even though I had a slow-start Balmar regulator
I just changed belts often - even after professional alignment checking, each time I accelerated the engine, the belt slipped until the alternator caught up.
The answer, I found years later, was a toothed high power belt. Change out the drive pulley, install a dedicated toothed drive pulley, and you won't eat any more belts.
BTW, both my 3GM35F engines failed after 5000 hours due to excessive heat. The extra power demands were more than the engine cooling
would support. Even after the rebuilds, the setup was less costly than an auxiliary generator
. And, it provided underway air conditioning
, a washer and dryer, and ample power
via 1200 Ah of flooded cells and a 3kW inverter