Transmission Position Under Sai

[Richard Gelfand]

What is the best position for the transmission while under sail? Neutral, forward or reverse for a Yanmar YSB8.



Aldajon@aol.com

[Duncan Maio]

What is the best position for the transmission while under sail? Neutral, forward or reverse for a Yanmar YSB8.

Well, neutral will allow the prop to freewheel, which will reduce drag and increase speed. It will also increase wear on the transmission bearings, which don't get proper lubrication if the engine isn't running. I prefer reverse, because the shift lever is more out of the way than in forward on my CD27.

Duncan Maio
s/v Remedy
CD27 #37



dmaio@att.net

[sam]

My hurth xmsn says either neutral or reverse but not fwd. I too prefer reverse. Besides 'wear and tear' you don't get the noise of a freewheeling prop.

[Bill]

My owners manual states that the boat should be in reverse when under sail!!

BS

What is the best position for the transmission while under sail? Neutral, forward or reverse for a Yanmar YSB8.

cd25d@clnk.com

[Ed Haley]

I use reverse gear when sailing. If the gear is in neutral, the free-wheeling prop will cause wear on the stuffing box packing and thus hastening "tweaking" time.



eghaley@dreamscape.com

[Walt Bilofsky]

What is the best position for the transmission while under sail? Neutral, forward or reverse for a Yanmar YSB8.

Well, neutral will allow the prop to freewheel, which will reduce drag and increase speed. It will also increase wear on the transmission bearings, which don't get proper lubrication if the engine isn't running. I prefer reverse, because the shift lever is more out of the way than in forward on my CD27.

Seems to me I saw somewhere that locking the prop actually produces less drag than letting it freewheel, because of the energy that freewheeling wastes in turning the prop and shaft.

'Scuse the powerboater's ignorance, but if you've got a two blade prop, is there a way to line it up with the keel (presumably minimizing drag) and lock it in gear - maybe a mark on the propshaft inside the boat?



bilofsky@toolworks.com

[Joe Wysong]

What is the best position for the transmission while under sail? Neutral, forward or reverse for a Yanmar YSB8.

Well, neutral will allow the prop to freewheel, which will reduce drag and increase speed. It will also increase wear on the transmission bearings, which don't get proper lubrication if the engine isn't running. I prefer reverse, because the shift lever is more out of the way than in forward on my CD27.

Seems to me I saw somewhere that locking the prop actually produces less drag than letting it freewheel, because of the energy that freewheeling wastes in turning the prop and shaft.

'Scuse the powerboater's ignorance, but if you've got a two blade prop, is there a way to line it up with the keel (presumably minimizing drag) and lock it in gear - maybe a mark on the propshaft inside the boat?

Walt,

You are correct. A prop in a fixed position produces less drag than one in free wheeling. Tank test after tank test has proven this to be true.

I don't know about smaller CDs, but on my 330, lining the shaft up so that a two blade prop is in harmony with the rudder would take far more time and energy than it is worth. If you want to get there in a hurry, don't buy a Cape Dory.

Joe



tgjournal@gestalt.org

[Duncan Maio]

Seaworthy, one of the Boat/US publications, recently published a little sidebar about a 1995 study in Marine Technology and SNAME News (vol.32, #3), about propellers on small to mid-size sailboats.

On the subject of freewheeling: "The conclusion from these calculations [and tests] is that a substantial reduction in drag, and thus gains in boat speed, can be realized when a fixed pitch propeller is allowed to freewheel. The decision to freewheel or not, though, must also take into account the factors of noise and wear and tear on the engine and bearings."

Duncan Maio
s/v Remedy
CD27 #37



dmaio@att.net

[Ed Haley]

My Cape Dory 28 is not known for being a speed queen but she's no slouch either. If fact, I could almost say she's "a spirited yacht." After years of sailing Jasmine, I can set a proper trim to make her romp through the surf. I feel it when I loosen a halyard or tweak a sheet. I hear the shusssh of water alongside the bow become a little louder. I can feel her lurch forward when topping a wave. Even though I've achieved maybe a half a knot faster to hit 6.5 knots, I still get a few goosebumps knowing things are working together well. Someone may be watching her and comments how pretty she looks dancing along the cat's paws.
.
If I can mark my prop shaft to get my two-bladed prop vertical, perhaps I'll gain a quarter knot. In doing so, I'll do justice to Jasmine and all others who look upon her sailing smartly along. I think these feelings are common to most sailors regardless of the type of boat. It's not really how fast you sail. It's how you sail fast.



eghaley@dreamscape.com

[Joe Wysong]

Seaworthy, one of the Boat/US publications, recently published a little sidebar about a 1995 study in Marine Technology and SNAME News (vol.32, #3), about propellers on small to mid-size sailboats.

On the subject of freewheeling: "The conclusion from these calculations [and tests] is that a substantial reduction in drag, and thus gains in boat speed, can be realized when a fixed pitch propeller is allowed to freewheel. The decision to freewheel or not, though, must also take into account the factors of noise and wear and tear on the engine and bearings."

Duncan Maio
s/v Remedy
CD27 #37

Don't believe everything you read, either in Seaworthy or The New York Times.

Joe



tgjournal@gestalt.org

[Neil Gordon]

>>If you want to get there in a hurry, don't buy a Cape Dory.<<

But if you want to get there, regardless of the unpredicted wind and waves you run into, that's a different story.


Regards, Neil
s/v LIQUIDITY
Cape Dory 28 #167



neil@nrgordon.com

[sam]

Reading the discussion of fast or only half fast, I assume all you 'fast' sailors out there also dry sail the boat or dive down to clean the bottom off routinely?? If not I would bet you are losing more speed from hull drag than prop drag. Also keep in mind the prop is partly hidden by the hull on a CD. Unlike a fin keel boat where it is out is the open.

[John]

>> Touche !!!

>>If you want to get there in a hurry, don't buy a Cape Dory.<<

But if you want to get there, regardless of the unpredicted wind and waves you run into, that's a different story.


Regards, Neil
s/v LIQUIDITY
Cape Dory 28 #167

nuttallj@msn.com

[sam]

Having read all the discussion on this interesting topic, I would like to offer one other approach for maximizing speed. Rather than aligning your 2 bladed prop, I suggest you could jump overboard and remove the prop after you clear the harbor. Tests show a boat with no prop has less drag than any of the other alternatives. When you return it is an easy matter to jump overboard again and re-attach the prop.

Not only does this provide more speed but it also makes your sailing time far more pure- like they used to do in the old days. So heres to tradition!

Sorry I couldn't resist this and no one is going to read this anyway as the topic is too old.

[Jerry Hammernik]

Sorry I couldn't resist this and no one is going to read this anyway as the topic is too old.

You're wrong, some of us read almost everything! I take it you're not sailing on Lake Michigan. We generally base much of our sailing activities on staying out of that cold water. But if you do remove the prop, be sure to place a smooth covering over the threads on the end of the prop shaft. (turbulance, you know);-] Oh well, we have to talk about something until spring!
Good Sailing,
Jerry



dauntles@execpc.com