What size props?

[TonyO]

We've recently bought a 1984 Fairline Sunfury fitted with single diesel. The engine is a Volvo AQAD40B and the sterndrive is a Duoprop (290?). I suspect that the boat's currently fitted with A2 props. The boat quickly reaches cruising revs (3400) and then slowly accelerates to max (3600) with a top speed of just over 18 knots.

What props can I fit to the boat (other than A2s) and what would the advantages/disadvantages be of the different choices. I know nothing about prop selection!

Many thanks for any assistance.

Tony

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[snowleopard]

sounds as though it's about the right prop for your boat. if the pitch was too fine it would run instantly up to max revs, if too coarse it would never get there and would give black smoke.

a larger prop with finer pitch will give more push in a chop while a smaller coarser one will give better top speed in flat water. with an outdrive you won't have much option on prop diameter.

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