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Keep the propeller fixed or let it turn?
My brother in law, and I have had a discussion of whether it
is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure .... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). Anybody in this group that can convince one of us, that he is not right? ... -- Flemming Torp |
"Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing I always put the transmission in reverse when sailing. I don't think that my Yanmar book says anything, but when I sailed on a friend's Cape Dory, he said to always do so due the gearbox that he had. Leanne |
It has been repeatedly demonstrated that airplanes glide significantly
farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. It also agrees with just about every other reference I've seen on the subject. -- Roger Long "Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). Anybody in this group that can convince one of us, that he is not right? ... -- Flemming Torp |
"Leanne" skrev i en meddelelse ... "Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing I always put the transmission in reverse when sailing. I don't think that my Yanmar book says anything, but when I sailed on a friend's Cape Dory, he said to always do so due the gearbox that he had. Leanne So do I - when cruising, but that is not my point ... The question is: (If I race for instance): Will I increase the speed of the boat by letting the propeller turn without resistance? Or should I stop it from turning? -- Flemming Torp |
"Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. "Leanne" skrev i en meddelelse ... "Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing I always put the transmission in reverse when sailing. I don't think that my Yanmar book says anything, but when I sailed on a friend's Cape Dory, he said to always do so due the gearbox that he had. Leanne So do I - when cruising, but that is not my point ... The question is: (If I race for instance): Will I increase the speed of the boat by letting the propeller turn without resistance? Or should I stop it from turning? -- Flemming Torp It's a fact that a spinning prop creates far more drag that a stopped prop. CN |
There is no easy way to prove this one way or the other by hand waving
for one reason: it depends on the propeller. Large ship propellers are sometimes more efficient freewheeling, but this is not the case for 3-blade yacht props. I suspect the the difference has to do with the pitch, and whether or not the flow is stalled - Ship props often high a large pitch compared to yacht props. BTW, it worth while lining up one blade of a 3-blade with the hull when you lock it. Flemming Torp wrote: My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). Anybody in this group that can convince one of us, that he is not right? ... |
"Gary L. Burnore" wrote in message ... On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. I used to fly an ultralight aircraft - a Rotec Rally 2B. It had a two-bladed wood prop that was driven by a Kohler air-cooled 432cc two-stroke engine via a centrifugal clutch and belt. I could climb to about two or three thousand feet and shut off the motor and the propeller would free-wheel because of the centrifugal clutch being disengage. The glide ratio was terrible with the prop free wheeling - one could feel the drag it caused. I put a brake on the clutch hub and stopped the prop from free-wheeling and the glide ration increased dramatically. The same extra drag is evident on a boat propeller that free-wheels. It's as if the two blades turn into a fixed disk. CN |
Pardon Sir, You can't feather a prop on a Cessna 152/172, Piper 140,
Piper Warrior, etc. But the engine out procedure is to stop the prop for max glide distance due to less drag as the previous post explained. Air is a fluid like water, just lighter. Lee Gary L. Burnore wrote: On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. -- gburnore@databasix dot com -------------------------------------------------------------------------= -- How you look depends on where you go. -------------------------------------------------------------------------= -- Gary L. Burnore | =DD=DB=B3=BA=DD=B3=DE=B3=BA=DD= =B3=B3=DD=DB=BA=DD=B3=DE=B3=BA=DD=B3=DD=B3=DE=B3=B A=DD=B3=DD=DD=DB=B3 | =DD=DB=B3=BA=DD=B3=DE=B3=BA=DD= =B3=B3=DD=DB=BA=DD=B3=DE=B3=BA=DD=B3=DD=B3=DE=B3=B A=DD=B3=DD=DD=DB=B3 DataBasix | =DD=DB=B3=BA=DD=B3=DE=B3=BA=DD= =B3=B3=DD=DB=BA=DD=B3=DE=B3=BA=DD=B3=DD=B3=DE=B3=B A=DD=B3=DD=DD=DB=B3 | =DD=DB=B3 3 4 1 4 2 =DD=B3=DE= =B3 6 9 0 6 9 =DD=DB=B3 Black Helicopter Repair Svcs Division | Official Proof of Purchase =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D= =3D Want one? GET one! http://signup.databasix.com =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D= =3D |
"Capt. Neal®" wrote in message ... "Gary L. Burnore" wrote in message ... On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. I used to fly an ultralight aircraft - a Rotec Rally 2B. It had a two-bladed wood prop that was driven by a Kohler air-cooled 432cc two-stroke engine via a centrifugal clutch and belt. I could climb to about two or three thousand feet and shut off the motor and the propeller would free-wheel because of the centrifugal clutch being disengage. The glide ratio was terrible with the prop free wheeling - one could feel the drag it caused. I put a brake on the clutch hub and stopped the prop from free-wheeling and the glide ration increased dramatically. The same extra drag is evident on a boat propeller that free-wheels. It's as if the two blades turn into a fixed disk. CN You guys need to get a room. John Cairns |
"John Cairns" wrote in message .. . "Capt. Neal®" wrote in message ... "Gary L. Burnore" wrote in message ... On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. I used to fly an ultralight aircraft - a Rotec Rally 2B. It had a two-bladed wood prop that was driven by a Kohler air-cooled 432cc two-stroke engine via a centrifugal clutch and belt. I could climb to about two or three thousand feet and shut off the motor and the propeller would free-wheel because of the centrifugal clutch being disengage. The glide ratio was terrible with the prop free wheeling - one could feel the drag it caused. I put a brake on the clutch hub and stopped the prop from free-wheeling and the glide ration increased dramatically. The same extra drag is evident on a boat propeller that free-wheels. It's as if the two blades turn into a fixed disk. CN You guys need to get a room. John Cairns Did you go skiing again this winter? Did your break your leg again? I'm telling you, KKKaty, ya gotta watch that osteoporosis since you're post-menopausal. CN |
"Capt. ****®" displaying symptoms of senile dementia, spewed the following ... "John Cairns" wrote in message .. . "Capt. Neal®" wrote in message ... "Gary L. Burnore" wrote in message ... On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. I used to fly an ultralight aircraft - a Rotec Rally 2B. It had a two-bladed wood prop that was driven by a Kohler air-cooled 432cc two-stroke engine via a centrifugal clutch and belt. I could climb to about two or three thousand feet and shut off the motor and the propeller would free-wheel because of the centrifugal clutch being disengage. The glide ratio was terrible with the prop free wheeling - one could feel the drag it caused. I put a brake on the clutch hub and stopped the prop from free-wheeling and the glide ration increased dramatically. The same extra drag is evident on a boat propeller that free-wheels. It's as if the two blades turn into a fixed disk. CN You guys need to get a room. John Cairns Did you go skiing again this winter? Did your break your leg again? I'm telling you, KKKaty, ya gotta watch that osteoporosis since you're post-menopausal. **** Okay, since Steve and Gary won't help, I will. Look carefully below: Path: newssvr33.news.prodigy.com!newsdbm06.news.prodigy. com!newsdst02.news.prodigy.com!newsmst01b.news.pro digy.com!prodigy.com!postmaster.news.prodigy.com!n ewssvr33.news.prodigy.com.POSTED!e2e32dd9!not-for-mail From: "John Cairns" Newsgroups: rec.boats.cruising,alt.usenet.kooks,alt.sailing.as a References: Subject: Keep the propeller fixed or let it turn? Lines: 41 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-RFC2646: Format=Flowed; Response Message-ID: NNTP-Posting-Host: 69.212.172.51 X-Complaints-To: X-Trace: newssvr33.news.prodigy.com 1118024857 ST000 69.212.172.51 (Sun, 05 Jun 2005 22:27:37 EDT) NNTP-Posting-Date: Sun, 05 Jun 2005 22:27:37 EDT Organization: SBC http://yahoo.sbc.com X-UserInfo1: TSU[@ION_ZWURVLX\RHBNFXBWR\HPCTL@XT^OBPLAH[\RSAANVUEAE[YETZPIWWI[FCIZA^NBFXZ_D[BFNTCNVPDTNTKHWXKB@X^B_OCJLPZ@ET_O[G\XSG@E\G[ZKVLBL^CJINM@I_KVIOR\T_M_AW_M[_BWU_HFA_]@A_A^SGFAUDE_DFTMQPFWVW[QPJN Date: Mon, 06 Jun 2005 02:27:37 GMT Xref: newsmst01b.news.prodigy.com rec.boats.cruising:257982 alt.usenet.kooks:953006 alt.sailing.asa:396848 See the line that reads "NNTP-Posting-Host". Remember the number sequence. From: "katysails" Newsgroups: alt.sailing.asa References: m .com .com Subject: Boat built in desert a dream come true Lines: 17 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-RFC2646: Format=Flowed; Original Message-ID: Date: Sun, 13 Feb 2005 21:44:50 GMT NNTP-Posting-Host: 12.75.54.156 X-Complaints-To: X-Trace: bgtnsc04-news.ops.worldnet.att.net 1108331090 12.75.54.156 (Sun, 13 Feb 2005 21:44:50 GMT) NNTP-Posting-Date: Sun, 13 Feb 2005 21:44:50 GMT Organization: AT&T Worldnet Notice anything there? Read them twice if you're getting confused. Now, I'll let you get some sleep, they come around early in the a.m. to empty the dumpster behind the Winn-Dixie, wouldn't want to deprive you of your breakfast. John Cairns |
On Mon, 06 Jun 2005 03:44:41 GMT, "John Cairns"
wrote: "Capt. ****®" displaying symptoms of senile dementia, spewed the following ... "John Cairns" wrote in message .. . "Capt. Neal®" wrote in message ... "Gary L. Burnore" wrote in message ... On Sun, 05 Jun 2005 21:59:29 GMT, "Roger Long" top posted like a ****ing moron and wrote: It has been repeatedly demonstrated that airplanes glide significantly farther (up to 20%) when the nose is raised to slow them down enough to stop the prop and best glide speed is then resumed. I can't see any reason why this wouldn't be true of boat propellers as well. Because aircraft are entirely in the air an boats are partially in water. Airplane props are feathered, boat props aren't. I used to fly an ultralight aircraft - a Rotec Rally 2B. It had a two-bladed wood prop that was driven by a Kohler air-cooled 432cc two-stroke engine via a centrifugal clutch and belt. I could climb to about two or three thousand feet and shut off the motor and the propeller would free-wheel because of the centrifugal clutch being disengage. The glide ratio was terrible with the prop free wheeling - one could feel the drag it caused. I put a brake on the clutch hub and stopped the prop from free-wheeling and the glide ration increased dramatically. The same extra drag is evident on a boat propeller that free-wheels. It's as if the two blades turn into a fixed disk. CN You guys need to get a room. John Cairns Did you go skiing again this winter? Did your break your leg again? I'm telling you, KKKaty, ya gotta watch that osteoporosis since you're post-menopausal. **** Okay, since Steve and Gary won't help, I will. Look carefully below: Path: newssvr33.news.prodigy.com!newsdbm06.news.prodigy .com!newsdst02.news.prodigy.com!newsmst01b.news.pr odigy.com!prodigy.com!postmaster.news.prodigy.com! newssvr33.news.prodigy.com.POSTED!e2e32dd9!not-for-mail From: "John Cairns" Newsgroups: rec.boats.cruising,alt.usenet.kooks,alt.sailing.as a References: Subject: Keep the propeller fixed or let it turn? Lines: 41 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-RFC2646: Format=Flowed; Response Message-ID: NNTP-Posting-Host: 69.212.172.51 X-Complaints-To: X-Trace: newssvr33.news.prodigy.com 1118024857 ST000 69.212.172.51 (Sun, 05 Jun 2005 22:27:37 EDT) NNTP-Posting-Date: Sun, 05 Jun 2005 22:27:37 EDT Organization: SBC http://yahoo.sbc.com X-UserInfo1: TSU[@ION_ZWURVLX\RHBNFXBWR\HPCTL@XT^OBPLAH[\RSAANVUEAE[YETZPIWWI[FCIZA^NBFXZ_D[BFNTCNVPDTNTKHWXKB@X^B_OCJLPZ@ET_O[G\XSG@E\G[ZKVLBL^CJINM@I_KVIOR\T_M_AW_M[_BWU_HFA_]@A_A^SGFAUDE_DFTMQPFWVW[QPJN Date: Mon, 06 Jun 2005 02:27:37 GMT Xref: newsmst01b.news.prodigy.com rec.boats.cruising:257982 alt.usenet.kooks:953006 alt.sailing.asa:396848 See the line that reads "NNTP-Posting-Host". Remember the number sequence. From: "katysails" Newsgroups: alt.sailing.asa References: m s.com s.com Subject: Boat built in desert a dream come true Lines: 17 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-RFC2646: Format=Flowed; Original Message-ID: Date: Sun, 13 Feb 2005 21:44:50 GMT NNTP-Posting-Host: 12.75.54.156 X-Complaints-To: X-Trace: bgtnsc04-news.ops.worldnet.att.net 1108331090 12.75.54.156 (Sun, 13 Feb 2005 21:44:50 GMT) NNTP-Posting-Date: Sun, 13 Feb 2005 21:44:50 GMT Organization: AT&T Worldnet Notice anything there? Read them twice if you're getting confused. Now, I'll let you get some sleep, they come around early in the a.m. to empty the dumpster behind the Winn-Dixie, wouldn't want to deprive you of your breakfast. WD is still in business? They pulled out of my area two years ago. Figured they'd be 404 by now. John Cairns -- Let any real Christians reading here join me in prayer that the Lord would reward the foul imp posting as "Fred Hall" according to his works. Pastor Winter |
"Flemming Torp" fletopkanelbolle2rp.danmark wrote in
: Anybody in this group that can convince one of us, that he is not right? ... Let the boat drive the prop when sailing. That shaft produces 15-25A of DC power on Lionheart from her shaft-driven alternator. No sense wasting good power draggin' a stalled prop behind you. Lionheart's Perkins 4-108 transmission has been freewheeling because of her shaft alternator since 1986. Doesn't seem to have hurt it a bit. Look over in alt.binaries.pictures.sports.ocean at the engine room on Lionheart under the center cockpit. The shaft alternator is driven by a flat belt from a large pulley on the shaft. At 8 knots, the special alternator, itself, is turning about 200 RPM. To get the engine started, you must turn off the excitation current to this shaft alternator so you can remove the keyring from its switch to move the keyring to the engine control panel to crank the diesel. This makes sure you have secured the shaft alternator before starting the engine....captain proof. |
In article ,
fletopkanelbolle2rp.danmark says... My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). 1. Many transmissions require a running engine to keep them lubricated. Such transmissions should be locvked in reverse to prevent freewheeling. 2. A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. |
"Larry W4CSC" wrote
Look over in alt.binaries.pictures.sports.ocean at the engine room on Lionheart under the center cockpit. (snip) This makes sure you have secured the shaft alternator before starting the engine....captain proof. Gee, isn't this kind of "niggling and perfectionist", to quote a well respected rec.boats contributor? Of course, there is nothing wrong with that:) -- Roger Long |
Gogarty wrote:
In article , fletopkanelbolle2rp.danmark says... My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). 1. Many transmissions require a running engine to keep them lubricated. Such transmissions should be locvked in reverse to prevent freewheeling. This is not what he asked. He said specifically from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) Plus not all transmissions can be locked in reverse to prevent freewheeling. Ours cannot. Doesn't matter what gear you stop in, the shaft will freewheel unless you stop it by putting a vice grip on the shaft or something (IMHO a bad idea, but I know someone who does this). 2. A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. This is probably a good analogy, although not all aircraft principles will translate to water and v.v. (as the Wright brothers found) My answer would be the same as yours and also that if you have a two blade prop, it should be locked in line with the keel if it is possible to determine where that is etc. In our case, the freewheeling prop made so much noise that one of the first things we did was get a feathering prop. We do have evidence that feathering the prop increases our sailing speed, in addition to being quieter. grandma Rosalie |
"Dave" wrote in message ... On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. FOOL! Rotating in the same direction, yes. Producing lift, no. They only produce drag because of the angle of attack. CN |
On 6 Jun 2005 09:48:03 -0500, Dave wrote:
On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. Hmmmm, so Dave feels that a boat prop will reverse direction if the drive is placed in neutral from forward, while under way? Brian Whatcott Altus, OK |
"Brian Whatcott" skrev i en meddelelse ... On 6 Jun 2005 09:48:03 -0500, Dave wrote: On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. Hmmmm, so Dave feels that a boat prop will reverse direction if the drive is placed in neutral from forward, while under way? Brian Whatcott Altus, OK Being a sailor with no experience with aviation, I do not understand the helicopter analogy. In my opinion, a helicopter driven by the engine corresponds in my understanding to a sailboat, where the propeller is set to drive the boat *backwards* ..... When the propeller on the boat 'gets the chance' to run without the force of the motor, that is just sailing forward by sail, I expect the propeller to turn in the opposite direction ... that is 'forward' ... If that happens in a helicopter, I would expect the helicopter to hit the ground very fast ... don't you? I do not assume, that there is a lot of inertia in a propeller or shaft en a sailboat - may be that is the case in a helicopter, and that could explain the smooth landing without the assistance from the motor - or I'm I completely wrong here? ... -- Flemming Torp |
"Larry W4CSC" skrev i en meddelelse ... "Flemming Torp" fletopkanelbolle2rp.danmark wrote in : Anybody in this group that can convince one of us, that he is not right? ... Let the boat drive the prop when sailing. That shaft produces 15-25A of DC power on Lionheart from her shaft-driven alternator. No sense wasting good power draggin' a stalled prop behind you. Larry, I certainly enjoy most of your constructive and 'witty' comments in this newsgroup, and I learn a lot and from them. But this comment does not adress my question: ... When will my boat run fastest: 'Free' running propeller or fixed/locked propeller? ... Simple question, complicated answers, I understand ... I know this is a very partial question ... but that is to keep the issue as simple as possible ... *just speed* ... no economy or energy considerations, no maintenance og mechanic considerations, no ecology or noise consideration - I'm just interested in understand the relation between the status of the propeller and the speed og the boat - all other things equal ... -- Flemming Torp |
"Mike G" skrev i en meddelelse ews.com... In article , says... On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. I just have to ask. In what way is it a bad analogy? SNIP Personally I figure, locked or freewheeling, the difference in the amount of drag caused by a kicker's prop is going to be so small as to be a total non issue unless you are into times in parts of a second in which case you pull the damn thing out of the water anyway. -- Mike G. Heirloom Woods www.heirloom-woods.net I agree, that the practical difference might be dismissal .... but in a race every second counts per NM ... and it is not easy to get a fixed propeller out of the water ;-) - and I'm pretty curious of knowing the correct answer to my question - preferably backed by solid science as I'm not a scientist ... When cruising, I would always lock the propeller - or follow Larry's advice - use the energy generated ... that is something I will consider ti implement in the future ... -- Flemming Torp |
In article , "Flemming
Torp" fletopkanelbolle2rp.danmark says... Being a sailor with no experience with aviation, I do not understand the helicopter analogy. In my opinion, a helicopter driven by the engine corresponds in my understanding to a sailboat, where the propeller is set to drive the boat *backwards* ..... When the propeller on the boat 'gets the chance' to run without the force of the motor, that is just sailing forward by sail, I expect the propeller to turn in the opposite direction ... that is 'forward' ... If that happens in a helicopter, I would expect the helicopter to hit the ground very fast ... don't you? I do not assume, that there is a lot of inertia in a propeller or shaft en a sailboat - may be that is the case in a helicopter, and that could explain the smooth landing without the assistance from the motor - or I'm I completely wrong here? ... The boat prop continues to turn in the same direction as it did when it was the method of propulsion since there is no change in direction of the water flow. In other words nothing forcing it to counter rotate. In the case of the helicopter technically you are correct and a reversal of direction would change the rotation of the blades. However the rotors are connected to the engine via gears and can only rotate in the "lift" direction. When the helicopter starts to fall due to loss of power the rotors, slowed buy the drag of gears and engine, are forced to spin in the lift direction causing "drag" that slows the copter to a rate where impact with the ground is, at least, survivable. -- Mike G. Heirloom Woods www.heirloom-woods.net |
"Dave" skrev i en meddelelse ... On Mon, 6 Jun 2005 13:06:28 -0400, Mike G said: I just have to ask. In what way is it a bad analogy? Possibly you are thinking the freewheeling prop would somehow generate some forward motion. Not likely or you would have a perpetual motion machine. Those with an understanding of basic physics will understand my point. It's clear that a detailed explanation to you would be pointless, as you would have figured it out by now if you had the basic understanding. Please give it a try anyway ... please ... ;-) ... I'm curious, but not a physicist ... -- Flemming Torp |
"Mike G" skrev i en meddelelse ews.com... In article , "Flemming Torp" fletopkanelbolle2rp.danmark says... Being a sailor with no experience with aviation, I do not understand the helicopter analogy. In my opinion, a helicopter driven by the engine corresponds in my understanding to a sailboat, where the propeller is set to drive the boat *backwards* ..... When the propeller on the boat 'gets the chance' to run without the force of the motor, that is just sailing forward by sail, I expect the propeller to turn in the opposite direction ... that is 'forward' ... If that happens in a helicopter, I would expect the helicopter to hit the ground very fast ... don't you? I do not assume, that there is a lot of inertia in a propeller or shaft en a sailboat - may be that is the case in a helicopter, and that could explain the smooth landing without the assistance from the motor - or I'm I completely wrong here? ... The boat prop continues to turn in the same direction as it did when it was the method of propulsion since there is no change in direction of the water flow. In other words nothing forcing it to counter rotate. In the case of the helicopter technically you are correct and a reversal of direction would change the rotation of the blades. However the rotors are connected to the engine via gears and can only rotate in the "lift" direction. When the helicopter starts to fall due to loss of power the rotors, slowed buy the drag of gears and engine, are forced to spin in the lift direction causing "drag" that slows the copter to a rate where impact with the ground is, at least, survivable. -- Mike G. Heirloom Woods www.heirloom-woods.net I'm sorry - Now, I don't understand the argument or the analogy from the helicopter to the boat of my brother in law with three fixed blades ... Should he lock it or let it 'freewheel'? -- Flemming Torp |
In article , "Flemming
Torp" fletopkanelbolle2rp.danmark says... I agree, that the practical difference might be dismissal ... but in a race every second counts per NM ... and it is not easy to get a fixed propeller out of the water ;-) - and I'm pretty curious of knowing the correct answer to my question - preferably backed by solid science as I'm not a scientist ... When cruising, I would always lock the propeller - or follow Larry's advice - use the energy generated ... that is something I will consider ti implement in the future ... -- Flemming Torp Well, if you are racing and can't get the prop out of the water I can see where it may be of concern but if you're looking for a solid science answer I'd have to venture to say that there are so many variables involved only a practical application with the boat involved would work. Drag is drag and if you can set a straight course with a constant speed, difficult under sail even in ideal conditions but still do able, just locking and unlocking the prop and seeing what it does to your speed should provide the answer. However, I'd have to opine that there is a difference between a free wheeling prop and one that is not only spinning but driving an generator/alternator. There is no free ride. A prop working a generator requires more energy then a free wheeling one and the only place that energy can come from is the forward speed of the boat. Again, the difference may be negligible but if you are concerned with thousands of a second, as you would be if racing, you have now introduced one more variable that has to be considered. I'm afraid you can't really get a "just speed" answer and expect an answer backed by science without considering conservation of energy, every action has an......... and so on. I can't prove it but my money would be on a truly free spinning prop. A fixed prop wants to spin and is going to use energy trying to do so. It's going to fight forward motion harder then a free spinning prop. A prop with a generator on it will spin but not without the loss of energy required to also turn the generator, a free spinning prop requires only the energy required to spin it. It'll, pardon the pun, go with the flow. Some energy penalty but less then the first two scenario's Again, the only place the energy required can come from is the forward motion of the boat. -- Mike G. Heirloom Woods www.heirloom-woods.net |
Mike G wrote:
In article , says... On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. I just have to ask. In what way is it a bad analogy? Perhaps you should consider an autogyro: http://www.centennialofflight.gov/es...togyro/DI8.htm .... Personally I figure, locked or freewheeling, the difference in the amount of drag caused by a kicker's prop is going to be so small as to be a total non issue unless you are into times in parts of a second in which case you pull the damn thing out of the water anyway. Well, each to his own. It is often claimed that the difference can be up to a half of a knot. On a hundred mile passage that can be about an hour. Given a choice, I'd rather come in before dark. My previous boat had a two blade which I always locked aligned with the hull; my current boat has folding props. |
I'll try.
The answer will be found in conservation of energy. The energy books have to balance in every system. The amount if drag of the water flowing over the prop will exactly equal the energy being produced. With the prop stopped, it is simply pull aft on the shaft. The prop isn't very efficient that way. Try propelling a boat by putting the prop out ahead on a long line and then pulling it in quickly. When the prop is freewheeling, it is producing energy that is absorbed by heating up the bearings and lube oil in the transmission, (or in Larry's case by charging batteries). It's slightly counterintuitive but, whatever energy is produced has to have an exact mirror image in drag on the boat. Since the prop is making energy more efficiently while turning, there has to be more drag. -- Roger Long |
"Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. "Larry W4CSC" skrev i en meddelelse ... "Flemming Torp" fletopkanelbolle2rp.danmark wrote in : Anybody in this group that can convince one of us, that he is not right? ... Let the boat drive the prop when sailing. That shaft produces 15-25A of DC power on Lionheart from her shaft-driven alternator. No sense wasting good power draggin' a stalled prop behind you. Larry, I certainly enjoy most of your constructive and 'witty' comments in this newsgroup, and I learn a lot and from them. But this comment does not adress my question: ... When will my boat run fastest: 'Free' running propeller or fixed/locked propeller? ... Simple question, complicated answers, I understand ... I know this is a very partial question ... but that is to keep the issue as simple as possible ... *just speed* ... no economy or energy considerations, no maintenance og mechanic considerations, no ecology or noise consideration - I'm just interested in understand the relation between the status of the propeller and the speed og the boat - all other things equal ... -- Flemming Torp Lock the shaft for speed. Don't allow the prop to freewheel. It's that simple. CN |
"Roger Long" skrev i en meddelelse ... I'll try. The answer will be found in conservation of energy. The energy books have to balance in every system. The amount if drag of the water flowing over the prop will exactly equal the energy being produced. With the prop stopped, it is simply pull aft on the shaft. The prop isn't very efficient that way. Try propelling a boat by putting the prop out ahead on a long line and then pulling it in quickly. When the prop is freewheeling, it is producing energy that is absorbed by heating up the bearings and lube oil in the transmission, (or in Larry's case by charging batteries). It's slightly counterintuitive but, whatever energy is produced has to have an exact mirror image in drag on the boat. Since the prop is making energy more efficiently while turning, there has to be more drag. -- Roger Long Thank you for trying, Roger. Sorry, but I still have some doubts. In my opinion it requires quite a lot of energy just to keep the propeller fixed when sailing. It is not possible - for instance to hold the propeller shaft by hand - so the shaft does not turn - as Rosalie confirmed ... So there must be quite a constant pressure on the gear box, when just sailing and the prop locked by the gearbox. In my opinion, it could be compared to a kind of turbine, where you keep the blades fixed from turning ... My intuition tells me, however, that if you 'let the propeller go', the total resistance/drag will be less and if you start braking the turning propeller, the resistance/drag gets bigger, and that resistance can be converted to electricity - as explained by Larry -isn't that right? But I must admit, that I don't know - or may be worse: Don't understand - the Law of physics behind the right answer ... -- Flemming Torp PS - I have followed your interesting 'report' of the last few months of projects on your boat ... good and inspiring reading - thank you! |
In article , Gogarty wrote:
In article , fletopkanelbolle2rp.danmark says... My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). 1. Many transmissions require a running engine to keep them lubricated. Such transmissions should be locvked in reverse to prevent freewheeling. 2. A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. The analogys between aircraft and boat propellors do not hold up when examined by people who understand the physics involved. I have a very superficial understanding of the matter, but I can see several problems with it. An aircraft with a fixed pitch propellor will glide farther with the propellor stopped because the propellor is bolted directly to the engine crankshaft. If the prop is turning, the engine is turning. If the engine is dead but still being turned, the power to turn the engine is being extracted from the air flowing through the propellor. The power lost in turning the porpellor and engine shows up as drag in the airstream which requires a steeper and shorter glide to maintain a flyable airspeed. If the engine can be separated from the propellor by placing a transmission into neutral as I would expect the case to be in a sailboat, I would guess that a free wheeling prop would produce less drag than pulling the stalled propellor blades through the water. It should take very little power to turn a shaft riding in two or three bearings with no load on them. The turbulence of the stopped propellor blades dragging through the water at nearly right angles to their streamline shape should put up a lot more resistance. A helicopter rotor bears no resemblance to a boat propellor because the rotor blades have variable pitch that can change each blade individually. The pitch angle can be set so that (in one exampe) the blade that is moving forward has a very low pitch while the blade that is moving backward has a very high pitch. This means that the individual blades are constantly twisting and turning in their hub bearings as the entire rotor assembly goes around. There is nothing similar to that in any boat propellor that I have ever heard of. |
You sort of have to think in reverse. When locked, the blades are
like an airfoil at an angle of attack of nearly 90 degrees, not very efficient. When turning, the blades are at a low angle of attack and more efficient. A parachute is less efficient per unit area than a wing. When the prop freewheels, it's rotational speed makes the water flow over it faster than when it is just dragged through the water at boat speed. Whatever force is produced has to be reflected in drag on the boat as a whole. This is a very crude pointer towards understanding a complex set of relationships so, others, please don't bother jumping all over me to point out how it isn't a rigorous and complete explanation. There are a narrow range of conditions when a freewheeling prop may have less drag than a fixed one but they are not commonly encountered in actual vessels. -- Roger Long |
"Mike G" wrote in message
ews.com... In article , says... On Mon, 06 Jun 2005 08:01:55 -0400, Gogarty said: A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. Bad analogy. In a helicopter when the rotors are freewheeling after the engine dies they're still rotating in a direction that generates lift. I just have to ask. In what way is it a bad analogy? It's a bad analogy because a prop and a helicopter blade operate on different principles. A prop is simply a screw whereas a helicopter blade is an airfoil. When it rotates it generates lift in the same way that an airplane's wing does. THis is not the case with a prop. -- Peter Aitken |
"Mike G" skrev i en meddelelse ews.com... In article , "Flemming Torp" fletopkanelbolle2rp.danmark says... I agree, that the practical difference might be dismissal ... but in a race every second counts per NM ... and it is not easy to get a fixed propeller out of the water ;-) - and I'm pretty curious of knowing the correct answer to my question - preferably backed by solid science as I'm not a scientist ... When cruising, I would always lock the propeller - or follow Larry's advice - use the energy generated ... that is something I will consider ti implement in the future ... -- Flemming Torp Well, if you are racing and can't get the prop out of the water I can see where it may be of concern but if you're looking for a solid science answer I'd have to venture to say that there are so many variables involved only a practical application with the boat involved would work. Drag is drag and if you can set a straight course with a constant speed, difficult under sail even in ideal conditions but still do able, just locking and unlocking the prop and seeing what it does to your speed should provide the answer. That's exactly, what we have tried, but the conditions were not ideal, so we did not - unfortunately - come up with some 'conclusive empiric evidence' ... However, I'd have to opine that there is a difference between a free wheeling prop and one that is not only spinning but driving an generator/alternator. There is no free ride. A prop working a generator requires more energy then a free wheeling one and the only place that energy can come from is the forward speed of the boat. That's also what my intuition tells me, but listening to other people in this group, I get the impression, that my intuition is not valid in this case ... Again, the difference may be negligible but if you are concerned with thousands of a second, as you would be if racing, you have now introduced one more variable that has to be considered. I do not understand - a new variable? My question is simple: .... If all other things are equal, should I stop my propeller or should I let i turn freely? I'm afraid you can't really get a "just speed" answer and expect an answer backed by science without considering conservation of energy, every action has an......... and so on. I can't prove it but my money would be on a truly free spinning prop. A fixed prop wants to spin and is going to use energy trying to do so. It's going to fight forward motion harder then a free spinning prop. A prop with a generator on it will spin but not without the loss of energy required to also turn the generator, a free spinning prop requires only the energy required to spin it. It'll, pardon the pun, go with the flow. Some energy penalty but less then the first two scenario's Again, the only place the energy required can come from is the forward motion of the boat. -- Mike G. Heirloom Woods www.heirloom-woods.net My problem is, that I can not see, that your above argument is wrong ... but some other readers in this group tell me, it is not correct ... Unfortunately, I do not know/understand the laws of physics governing this situation .... -- Flemming Torp |
"Dave" skrev i en meddelelse ... On Mon, 06 Jun 2005 19:31:31 GMT, "Roger Long" said: When the prop is freewheeling, it is producing energy A fairly basic principle: energy can be neither created nor destroyed. Isn't it right, that when the boat is sailing (just for sail that is) you need some energy to keep the propeller from turning - i.e. to keep it fixed - and that gives a certain drag on the boat .... My intuition tells me that when you ' loosen the grip' on the propeller shaft and let the propeller turn freely, it reduces the drag on the boat. Right or wrong? -- Flemming Torp |
"Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. "Dave" skrev i en meddelelse ... On Mon, 06 Jun 2005 19:31:31 GMT, "Roger Long" said: When the prop is freewheeling, it is producing energy A fairly basic principle: energy can be neither created nor destroyed. Isn't it right, that when the boat is sailing (just for sail that is) you need some energy to keep the propeller from turning - i.e. to keep it fixed - and that gives a certain drag on the boat .... My intuition tells me that when you ' loosen the grip' on the propeller shaft and let the propeller turn freely, it reduces the drag on the boat. Right or wrong? You have lousy intuition, Flemming. CN |
"me" skrev i en meddelelse news:zn2pe.7783$nr3.5795@trnddc02... In article , Gogarty wrote: In article , fletopkanelbolle2rp.danmark says... My brother in law, and I have had a discussion of whether it is best - from a pure speed point of view (no consideration to the mechanics/oil/maintenance/gearbox etc. here ...) whether you should let your "fixed three bladed propeller" run/turn or keep it fixed (like put into gear) when sailing just for the wind with your sails in a 34 feet cruiser weighing roughly 5 T ... We have - unsuccesfully - tried to find out using the log ... the results were not conclusive - or one of us would not admit, that the other was right ... I think we need a testimony from someone, that has a 'scientific based valid answer' ... or just knows for sure ... The assumption is: There is no way to move, turn, 'collapse' anything on the propeller - the 'blades' are fixed ... (hard to explain in a language, that is not your own ... hope you get my point). 1. Many transmissions require a running engine to keep them lubricated. Such transmissions should be locvked in reverse to prevent freewheeling. 2. A freewheeling propeller creates more drag than a locked on.. Just consider a helicopter. Engine out and rotors freewheeling, the aircraft will go down safely. Rotors locked and it drops like a stone. The analogys between aircraft and boat propellors do not hold up when examined by people who understand the physics involved. I have a very superficial understanding of the matter, but I can see several problems with it. An aircraft with a fixed pitch propellor will glide farther with the propellor stopped because the propellor is bolted directly to the engine crankshaft. If the prop is turning, the engine is turning. If the engine is dead but still being turned, the power to turn the engine is being extracted from the air flowing through the propellor. The power lost in turning the porpellor and engine shows up as drag in the airstream which requires a steeper and shorter glide to maintain a flyable airspeed. If the engine can be separated from the propellor by placing a transmission into neutral as I would expect the case to be in a sailboat, I would guess that a free wheeling prop would produce less drag than pulling the stalled propellor blades through the water. It should take very little power to turn a shaft riding in two or three bearings with no load on them. The turbulence of the stopped propellor blades dragging through the water at nearly right angles to their streamline shape should put up a lot more resistance. A helicopter rotor bears no resemblance to a boat propellor because the rotor blades have variable pitch that can change each blade individually. The pitch angle can be set so that (in one exampe) the blade that is moving forward has a very low pitch while the blade that is moving backward has a very high pitch. This means that the individual blades are constantly twisting and turning in their hub bearings as the entire rotor assembly goes around. There is nothing similar to that in any boat propellor that I have ever heard of. I'm not sure I get your conclusion ... ;-) Sorry, but do you recommend me to let the propeller turn og should I stop it from turning, if I'm only concerned with the speed of the sailboat - when only using the sails? -- Flemming Torp |
Your intuition is wrong. You never loosen the grip, you just change
to a different kind of grip. Ever notice how hot brakes get? That's because they are turning all that energy into heat. When you let the prop go, it is still restrained by the friction of the bearings and oil in the transmission. They get warmer because they are turning the energy being produced into heat. That gets reflected in drag on the boat. When the prop is locked, the shaft break, clutch, or whatever is holding it doesn't get hotter. What gets hotter is the water flowing past the blades. That energy production gets reflected in drag on the boat as well but there is less of it at normal sailing speeds and freewheeling shaft rpm. -- Roger Long "Flemming Torp" fletopkanelbolle2rp.danmark wrote in message . .. My intuition tells me that when you ' loosen the grip' on the propeller shaft and let the propeller turn freely, it reduces the drag on the boat. Right or wrong? -- Flemming Torp |
OK, here is the answer you are looking for. Unless you have a highly unusual powertrain set up and strangely pitched prop, determine the position in which the most blade area is shadowed by keel and hull. Mark the shaft inside. Stop the shaft in that position. Sail the boat. It's very unlikely you'll go faster doing anything else. -- Roger Long |
"Roger Long" wrote in
: Gee, isn't this kind of "niggling and perfectionist", to quote a well respected rec.boats contributor? Oh, you'd have a fit if you looked into that bilge. There's dishwater, some oil, some rust, a few tools too deep to reach even with the magnet, how awful! It's a boat....not house beautiful. Everything from the sinks, shower, everything but the head, dumps in her bilge to be pumped overboard WITHOUT those nasty thru-hull fittings rotting away...(c; Look at the next picture. This is the NEW engine Cap bought from a guy in NC I met on this newsgroup. It's a pullout. See? We didn't even paint it! Looks awful...runs fantastic. The original looked worse. It had over 8000 hours on it. This "new" one is only up to 900 hours, now. Cap'n Geoffrey couldn't even destroy it trying to start it full of seawater when that stupid water injection line to the dripless packing he had a shipyard install BACKED UP seawater into the exhaust ports. Try sailing up Ponce Inlet S of Daytona Beach in the rush of an outgoing tide past the lighthouse and seawall so the tow operator can drag you all the way to Daytona Marina. Scary stuff that day. Cutter Doc did a great job pickling the engine. It looked like we pumped the Exxon Valdez oil slick out of the crankcase...(c; These pictures are old. I need to carry my camera down, now that she's been fitted out, and take some new pictures in her. I'm usually too busy when Geoffrey is around working on his to-do list...(c; He finally gave up trying to pay me. He asked what I wanted for all my work. I told him, "That's easy. Just take me with you." It's worked out great for both of us....(c; |
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