Greetings,
I have a CD27 with a Westerbeke M13 and trying to gather some information on props. Presently the M13 is attached to a Michigan Sailor 2-84 12X12 RH but doesn't appear to be putting all the engines power in the water. Would anyone out there have any experience with a differently pitched 2 blade, or perhaps a 3 blade? I believe the 12" diameter is the maximum for this boat.
Roger Bunker
CD27 "Temptress"
Kemah, TX.
roger.bunker@wcom.com
CD27 Prop Question
Moderator: Jim Walsh
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Al Smith
Re: CD27 Prop Question
We have a Cambell's Sailor prop on our CD33 and really like it alot. It gives excellent forward power and reverse power, but causes significantly less drag than other 3-bladed props do.
Al Smith
Elysium
Deltaville, Va
Al Smith
Elysium
Deltaville, Va
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jim stull
Re: CD27 Prop Question
Hi Roger
I spent a good bit of time on this issue. The question is hard to answer because it is not a "go or not go" issue. As you have experienced your boat does not achieve its potential due to the prop.
If you were not especially interested in, or did not require full performance under power the 12" prop would not be an issue with you. On the other hand, if you want to be able to get the most from your engine, it would be. You may need max power to buck a strong current, going up a river etc.
I have installed a 18hp Yanmar 2GM20F into the CD27 we are rebuilding. I used Michigan Wheel's Tech Dept. as a source of help. They very strongly recommended a 14", 3 blade prop to get the max out of the new engine. As you probably know there is a stainless bar in the rudder. I was very much afraid that if I cut away too much from the rudder, (and also the deadwood), I would have a problem. During my search for a rebuilable CD27 we inspected one that had had a Yanmar2GM installed. And it had been modified to take a 13", 3 blade prop.
I therefore pushed Mich. Wheel to do a "run" for a 13" prop. This they did and this is what I bought. But they still said that the 14" was required to get full engine potential.
The Yanmar installation manual provides a formula for prop clearance, which I tried to follow when I cut away the rudder and the deadwood. I have reglassed these areas and it looks "factory” now. I used a metal detector before cutting to avoid any surprises and the job was actually not very difficult once I started.
Jim
jtstull@earthlink.net
I spent a good bit of time on this issue. The question is hard to answer because it is not a "go or not go" issue. As you have experienced your boat does not achieve its potential due to the prop.
If you were not especially interested in, or did not require full performance under power the 12" prop would not be an issue with you. On the other hand, if you want to be able to get the most from your engine, it would be. You may need max power to buck a strong current, going up a river etc.
I have installed a 18hp Yanmar 2GM20F into the CD27 we are rebuilding. I used Michigan Wheel's Tech Dept. as a source of help. They very strongly recommended a 14", 3 blade prop to get the max out of the new engine. As you probably know there is a stainless bar in the rudder. I was very much afraid that if I cut away too much from the rudder, (and also the deadwood), I would have a problem. During my search for a rebuilable CD27 we inspected one that had had a Yanmar2GM installed. And it had been modified to take a 13", 3 blade prop.
I therefore pushed Mich. Wheel to do a "run" for a 13" prop. This they did and this is what I bought. But they still said that the 14" was required to get full engine potential.
The Yanmar installation manual provides a formula for prop clearance, which I tried to follow when I cut away the rudder and the deadwood. I have reglassed these areas and it looks "factory” now. I used a metal detector before cutting to avoid any surprises and the job was actually not very difficult once I started.
Jim
jtstull@earthlink.net
-
Fred
Re: CD27 Prop Question
a 3 blade prop might be more efficient motor-wise, but it will cause significantly more drag when proceeding under sail.
Roger Bunker wrote: Greetings,
I have a CD27 with a Westerbeke M13 and trying to gather some information on props. Presently the M13 is attached to a Michigan Sailor 2-84 12X12 RH but doesn't appear to be putting all the engines power in the water. Would anyone out there have any experience with a differently pitched 2 blade, or perhaps a 3 blade? I believe the 12" diameter is the maximum for this boat.
Roger Bunker
CD27 "Temptress"
Kemah, TX.