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  #1   IP: 24.119.211.241
Old 01-19-2021, 04:22 PM
Truchero Truchero is offline
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Prop size for Pearson Renegade 27?

What propeller size should I use with a Pearson Renegade 27 with the A4 engine? It's at a boatyard and I have never handled it under power. It came with a composite propeller installed, and also a 13x11 Michigan two blade brass prop in storage. The composite prop on the shaft is cracked. It has no numbers but it is significantly smaller than the brass one.

I initially planned to replace the broken one with the 13x11, but it seems like it would be too big for the low rpm engine. Any ideas? Can I get away with it? The boat has a 21' waterline and around 7k bare displacement.
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  #2   IP: 104.174.83.118
Old 01-19-2021, 05:32 PM
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If the engine is a direct drive (I expect it is), 13x11 is WAY too much prop. That's more of a reduction gear prop size. Direct drives usually have props with diameters between 10 and 12 inches with corresponding pitches of 8 to 6 inches, right hand rotation.
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prior boats 1987 Westsail 32, 1970 Catalina 22
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Old 01-19-2021, 05:56 PM
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Hey, welcome. As Neil said, too much prop. The composite is probably a CDI prop. The idea there was as you spun the prop and loaded it up, the blades would flatten and reduce pitch..the downside is they are fragile (IMO).

See if you can find something in the range Neil recommended..the boat is already on the hard, now is the time to replace the prop, and I would not put the 13 x 11 on there if I could find something new-to-me. Check eBay or one of the MANY sailboat salvage shops. Locally, I'd call Josh Davidson at Anchors & Oars in Stevensville, MD. He can probably ship too.

I run a 3-blade Indigo 10" x 7.4 pitch prop designed for the A-4. From a motoring perspective, I have been happy with it. I wish I had an adjustable pitch feathering prop that I could fine tune for motoring, and also help me out for light air sailing in the Chesapeake.
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Old 01-19-2021, 07:15 PM
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Here's what I have.

I have a C&C 30. My prop is a 3 blade Michigan 12/6. That is a great prop for my particular boat. I can back off my marina dock in 25 kts of wind coming on the stern with a row of boats behind me. I back it up behind those boats turning and using them as a wind break. Cut the power, shift to forward and throttle up...the boat starts going right now and I have way-on and steering in seconds. We have a few boats in our marina also with the Atomic 4. They all have two blade props and wouldn't even try that because it's a pretty tight spot when the wind is on the boat

That 12/6. It's a good combination for that particular boat. Good results in reverse although she does have a wicked prt side kick and lots of power to stand on right now. She's also good in chop off shore and keeps moving without too much effort.

I don't know what RPM's I get with the prop but I'm at 6.2 kts on a calm day just a tad above 1/2 throttle.
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Old 01-20-2021, 12:19 AM
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Thanks for the replies that I unfortunately knew were coming. I brought both propellers home and side by side they are nearly identical in size (12 in).
I donít know. I would have had to purchase a bushing anyhow (the brass one is for a 1Ē shaft, the boat has a 7/8Ē shaft). Hereís a pic of the props and a close up of the crack on the composite prop foR curiosity purposes.

Iím going to window shop on eBay to see what I find. Maybe a 3 blade prop? Who knows!

Iím in the process of sanding the whole boat down to repaint. Iíve repaired a significant amount of core and bulkhead rot, and filed a few thru holes. I also had to buy a main sail. I was just hoping to avoid having to buy a prop as well. Hopefully the engine is fine! Iím sure Iíll soon become a regular around these parts. Thanks again for the detailed info!
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  #6   IP: 104.174.83.118
Old 01-20-2021, 02:52 AM
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Check this out
https://www.ebay.com/itm/Sailboat-Pr...gAAOSwrlBfja5B
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1977 Catalina 30
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prior boats 1987 Westsail 32, 1970 Catalina 22
Had my hands in a few others
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Old 01-20-2021, 07:17 AM
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That a good deal there that Neil is showing you.
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1976 C&C 30 MKI

The pessimist complains about the wind.
The optimist expects it to change.
The realist adjusts the sails.
...Sir William Arthur Ward.
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Old 01-20-2021, 08:03 AM
Truchero Truchero is offline
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Quote:
Originally Posted by ndutton View Post
Thank you Neil, I purchased it within 30 seconds of seeing it!! One less thing to worry about. You guys are awesome! Iíll try to sell my prop too to mitigate the cost.
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