Thread: Prop question
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Old 02-26-2020, 06:19 AM   #20
rslifkin
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City: Rochester, NY
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Quote:
Originally Posted by Nomad Willy View Post
Archie wrote;
“No noticeable change in noise level.” Post 16

That’s what I’ve always thought.
I think noise from a diesel engine comes from load.
I worked in a powerhouse in 1960 w a 1400kw alternator driven by a 1400hp Enterprise diesel. It was noisy. And I noticed it was working at about 1/2 load. The straight 8 engine turned at 327rpm + or - 10. The governor was very very effective. It only lost 8-9rpm when it instantly went from 50% load to 90% load. It went instantly as it was the result of someone on the dredge flipping a switch turning on electric motors. And the noise seemed to double when they switched to the high pressure pumps down on the dredge. It sounded like you were near a diesel engine and instantly you were in a diesel engine. And almost NO change in rpm.
Agreed. More RPM increases noise some even with no load, but increased load has a much bigger difference with noise. This applies to gas or diesel for the most part.
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