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Connect engine to alternator, will it run? Answered

I have a new diesel 3 H.P engine and an 80 amp car type alternator, 12 volt.
A, will the engine run the alternator at full output to charge batteries?
B, Can I fit a bigger pulley to the engine?
Regards Brian.


Yes, and yes.

Yup In general a car alternator needs to run at around 3000 ROM to be efficient.

The alternator is ~1kW of output, the engine about 2.5kW, flat out. It shouldn't be too hard to do. Depending on the engine's power curve, you can mess around with the pulley, but I'm not sure it would be worth it.