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How is this not going to OVERLOAD the ENGINE?? | Ask The Expert with NIGEL CALDER
24 January 2026 · 5 min · 4K views
Nigel Calder demonstrates boat electrical system with alternator
What this video covers
Jan Attenstedt and Nigel Calder discuss the risks and benefits of pairing high-output alternators with over-pitched propellers on sailboats.▶ 0:27 Over-pitching a propeller improves fuel efficiency and reduces engine noise at cruising speeds by bringing the propeller power absorption curve closer to the engine's full power curve.▶ 0:54 However, this configuration risks engine damage if the vessel operates at wide-open throttle, as the engine may exceed its rated load, potentially burning out valves and pistons.▶ 1:43 Adding a high-output alternator creates an additional load that can further overload the engine as power demands increase.▶ 2:11 Modern programmable voltage regulators from manufacturers like Wakespeed, Zeus, and Altium mitigate this risk by monitoring engine RPM and automatically reducing or shutting down alternator output as the engine approaches its maximum load capacity.▶ 2:42 Properly configured systems allow for efficient power generation, reduced engine run hours, and decreased carbon buildup in conventionally injected engines.▶ 4:33
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