3 Blade prop

[Paul Breeding]

When I pull the boat this coming spring to repaint I am thinking of replacing the prop with a 3 blade (non-feathering, too many $$$). Does any one have experience, ideas, suggestions, pitfalls, etc. Any dialogue including specific manufacturers would be greatly appreciated. I will gladly trade off a little sailing speed for a little more punch when needed.

 

[Frank Conley]

3-Blade Prop for O'day 272

Paul,I sail south of Annapolis out of Herring Bay, changed from a 2-blade to 3-blade on my 272 two seasons ago and love it. Will get you the size and pitch from my records and post, I added one extra degree of pitch this summer over the original for some more punch. I have speed/rpm data for you also. There has not been a drop in sailing speed that I notice (can still get above 6 knots in best conditions)and my docking confidence has greatly increased with the extra bite of the 3-blade. I replaced my stuffing box with a dripless shaft seal at the same time and now have a completely dry engine bilge; another drive train improvement that I love (see archives and Bob Todd's posts to see his pictures of DIY shaft seal installation). How is your transmission doing, any slippage? I ended up rebuilding tranny, replacing wire gear/throttle linkage, new driveshaft coupling, stainless steel shaft + dripless shaft seal, cutlass bearing, and new prop in a complete rear drivetrain rebuild. With the new prop, boat is now totally responsive to all speed/gear change input instead of its old sloppiness (result: no more "acoustical dockings").Frank"Avanti", 1986 272

 

[Tom Ehmke]

Frank, please send me the information

about the 3-blade prop. How have you been? I think we go back at least a couple of seasons. You e-mailed me about something, but old-timer's disease has made my memory hazy. Glad to hear that you are enjoying your 272 as much as I do mine.Tom

 

[Brian R Clare]

Three Blade

Paul, I have a three blade on "Hosanna", definitely gives the right amount of punch with very good control in both directions. Have a super Thanksgiving, Brian.

 

[Paul Breeding]

THANKS

Brian, Frank & Tom,Thanks for your response re: 3 blade prop, it confirmed my thoughts. Now I need specifics to put the plan in motion by spring. Brian I have your address and will contact you directly, Frank you can reach me pbreedingco@pcisys.net, Tom I have pulled up your site in the past and gleaned over your mods. Happy Thanksgiving to all of you and the other O'Day'ers.

 

[Frank Conley]

272 3-Blade Prop Specs

Paul & Tom, sorry to take so long to get these specs. I installed a 12x7x3x7/8 RH Bronze MP Style Prop, after the first season we increased the pitch to 8 for a little more bite. Prop cost $293. My Westerbeke Ten2 turns 3600 RPM with no load and maxes at 3500 under load. I checked the knots/RPM while motoring in our channel and got the following readings on my GPS (no allowance for tide): 3.5/2000, 4.3/2500, 4.9/2800, 5.2/3000. I generally motor at 2800 RPM or 80% of loaded max RPM so I am getting around 5 knots in most conditions. Hope this helps,Frank

 

[Tom]

Thanks, Frank

The speeds you recorded SEEM to be a little higher then mine with the two blade. I usually run my 10-2 at 2800-3000rpm also. So... you think it was worth $300?Tom