Is bigger better? (Engine size) - SailNet Community
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post #1 of 3 Old 03-06-2009 Thread Starter
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Is bigger better? (Engine size)

I am new to Newports, and am looking at an 81 N30. It is mostly in good condition, but the engine is a Universal Diesel model 5411. My research show that standard engines in the N30 were 14-20hp, not 11hp of this motor.
I would appreciate any thoughts on whether this motor is powerful enough for this boat. (my cruising is the Puget Sound in WA). Also, I would appreciate your thought on engine noise, as this is one of the reasons my wife doesn't like going out in our current Catalina 25 w/ outboard.
Thanks in advance,
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post #2 of 3 Old 03-06-2009
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Bigger is better up to a point. The point is economy and hull speed driven.
The ideal is to be able to get to hull speed at the sweet spot in RPM where your engine is most efficient.
That point depends on engine, hull shape etc.
I would suggest that 11 hp is not up to snuff, especially in a head wind.

The rule of thumb is 2 hp per 1000 pound so weight, bringing you to 20 or so as a normal engine.

Lessons learned are opportunities earned.
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post #3 of 3 Old 03-06-2009
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The Womboat is 12,000lbs runs a Bukh DV24. Great little engine but if I were to re-engine then I'd go 30. Ours is 20 years old and the newer models tend to weigh less for the same output.

I'm sure that for getting in and out of a dock 11hp would do for that boat but it is as Chuckles pointed out going to struggle in adverse conditions.

Andrew B (Malö 39 Classic)

“Life is a trick, and you get one chance to learn it.”
― Terry Pratchett.
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