Work on bespoke Narrowboat ‘Ploddinon’ to improve the charging system. Spec of this new Barrus 50 engine looks impressive on paper with a 240 amp domestic alternator. In reality the owner has found the factory setup not up to modern live-aboard demands.


Charging voltage & current low. Belt squeak and squealing under high load on initial startup or running equipment off the inverter. Alternator’s non adjustable regulator set at low 14.2 ish Volts and large battery bank just not getting charged properly (taking time to reach even 14.0+V). The theoretical 240 amps is unobtainable due to low regulator voltage setting. And the solid alternator (non freewheeling) with narrow 6pk alternator pulley can’t reliably transmit more than around 100-130 amps at 12V. I bring it up to the same spec of a Beta Marine 43/50 engine fitting a quality 175amp Iskra Alternator with a freewheeling pulley. Now ~120 Amp+ at tickover with standard 14.6V regulator and the engine runs noticeably quieter and smoother. Install Adverc system adjusted to 14.8V (sensed at batteries ) to suit the Trojan battery bank. Engine charging system totally transformed and customer happy.



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