Will a High-Speed Prop Work on a Sailboat ?

[bazzer]

I need a new prop on my 35 foot boat with a Volvo MD17c, I have been offered a new super cupped Michigan 16 x 14 at a price I can afford. It it stupid to use it rather than a prop designed for a sailboat? At the moment the boat is overpropped and the maximum revs I can get is 2100. My gearbox is 1.91 to 1

[SkiprJohn]

I would not buy a high speed prop to use in a low speed application. I'd keep shopping. Used props should not be that expensive.
kind regards,

[Boracay]

I'm in a bit of a rush right now, but why not have a look through the manufacturer's web site and if you still have questions, ask them?

[bazzer]

Originally Posted by Boracay

I'm in a bit of a rush right now, but why not have a look through the manufacturer's web site and if you still have questions, ask them?

I'm trying to find out the difference. Surely a high speed prop should operate at low speeds just as well?

[capn_billl]

"Performs just as well", is a relative statement, you're replacing your existing prop because you don't like the performance.

[bazzer]

Originally Posted by capn_billl

"Performs just as well", is a relative statement, you're replacing your existing prop because you don't like the performance.

True, but I am cash short and the prop offers is a bargain at 250 bucks as opposed to 700. At the moment I am hopelessly over propped and can't get anywhere near hull speed

[Jim Cate]

Originally Posted by bazzer

True, but I am cash short and the prop offers is a bargain at 250 bucks as opposed to 700. At the moment I am hopelessly over propped and can't get anywhere near hull speed

Might be possible to have the existing prop re-pitched or reduced in diameter. Should not cost nearly as much as replacing.

Cheers,

Jim

[DaveOnCudjoe]

It's not just a question of performance but premature engine failure. If the engine is so overproped as to not be able to rev to full rpm then the engine is being lugged down and exhaust gas temperatures can exceed the melting point of components such as valves, valve seats and pistons. What's the cost of a rebuild? Dave

[bazzer]

Originally Posted by DaveOnCudjoe

It's not just a question of performance but premature engine failure. If the engine is so overproped as to not be able to rev to full rpm then the engine is being lugged down and exhaust gas temperatures can exceed the melting point of components such as valves, valve seats and pistons. What's the cost of a rebuild? Dave

I don't ever run the motor at more than half throttle with the existing prop, it gets me there but of course takes longer

[DeepFrz]

Oh, go ahead, just buy it. Let us know how it works out.

[markpierce]

Uhhh ... what propeller?

[chris07732]

You can use following prop calculators and convince yourself if the prop you are considering will give you the results you want. The calculations are very simple.

Also, as someone said above, re-pitching and reducing dia are relatively inexpensive and you can dial in the results you want using these calculators. I just had my 20x20 3 blade changed to a 19x18 to give me 400 extra rpm. Cost was $235 here in NJ

Boat Speed Calculator

Propeller Calculator / Prop Calculator

[bazzer]

Originally Posted by DeepFrz

Oh, go ahead, just buy it. Let us know how it works out.

Hey, I am just trying to find out what is the difference between a high speed prop and a sailboat prop. Surely one 16 x 14 prop and another 16 x 14 cupped prop is much the same except the cupped prop is more efficient is it not? My old prop, which was on the boat when I bought it is just about shot and I need to do something at the least cost.
Bazzer

[Chief Engineer]

High speed prop on a low speed boat.......

reverse the scenario and see if it makes sense.

Just another example of trying to beat the system for $$$ sake

[osirissail]

For some propeller 101 discussion See: Prop 101 | Precision Propellers Industries