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#11
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Hello again Thomas,
Let's dispell some more myths...and agree with some truths. We already know thae all boats do NOT have struts, particularly full-keel sailboats as opposed to fin-keeled....Many boats of higher -end construction(Nordhaven comes to mind,for instance) have bearings at the inner and outer end of the shaft log to reduce load on the TAILSHAFT bearing of the gearbox or reduction gear and to prevent "whipping of the shaft" ( a jump-rope-like effect) often caused by a long unsupported length of shaft and some misalignment-it doesn't take much-...Most commercial craft DO have strut and cutlass bearings; I have replaced many more than I care to count, having been in the marine service industry for the last 27+ years... The ceramic "face seal" that Steve refers to is a PSS "dripless shaft seal, and I see them far more often in pleasure boats than in Commercial applications. More commercial boats who have oil cooled upper bearings or standard logs use a TIDES type dripless seal, a lipseal very similar to a grease seal, this must be cooled by oil (the minority)or raw water which is engine supplied if available or supplied by a static siphon vent in keel- cooled apps, and typically with lower shaft RPM's (under 2000) The oil cooled stuffing boxes are becoming increasingly scarce on all but ships, they are environmentally detrimental as they leak oil to seawater intentionally, the approved versions are completely lubricant-captive and are quite expensive.The stand alone bearing and support Steve speaks of(Aqua-Drive) and similar has a twofold purpose: it allows major shaft misalignment to facilitate a variety of engine installations and it transfers thust directly to the stringers as Steve said...However, the vast-almost all-majority of propulsion engines are mounted on flexible,vibration dampening mounts, with or without an intermediate bearing and supports...in virtually all pleasurecraft and most small to medium commercial apps. ........But this is far more information than I think you were seeking...lol Good luck in whatever venture you decide to take on...Screw the NYYC types.... Best Regards, markvictor |
#12
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posted to rec.boats.building
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markvictor wrote:
Hello again Thomas, Let's dispell some more myths...and agree with some truths. We already know thae all boats do NOT have struts, particularly full-keel sailboats as opposed to fin-keeled....Many boats of higher -end construction(Nordhaven comes to mind,for instance) have bearings at the inner and outer end of the shaft log to reduce load on the TAILSHAFT bearing of the gearbox or reduction gear and to prevent "whipping of the shaft" ( a jump-rope-like effect) often caused by a long unsupported length of shaft and some misalignment-it doesn't take much-...Most commercial craft DO have strut and cutlass bearings; I have replaced many more than I care to count, having been in the marine service industry for the last 27+ years... The ceramic "face seal" that Steve refers to is a PSS "dripless shaft seal, and I see them far more often in pleasure boats than in Commercial applications. More commercial boats who have oil cooled upper bearings or standard logs use a TIDES type dripless seal, a lipseal very similar to a grease seal, this must be cooled by oil (the minority)or raw water which is engine supplied if available or supplied by a static siphon vent in keel- cooled apps, and typically with lower shaft RPM's (under 2000) The oil cooled stuffing boxes are becoming increasingly scarce on all but ships, they are environmentally detrimental as they leak oil to seawater intentionally, the approved versions are completely lubricant-captive and are quite expensive.The stand alone bearing and support Steve speaks of(Aqua-Drive) and similar has a twofold purpose: it allows major shaft misalignment to facilitate a variety of engine installations and it transfers thust directly to the stringers as Steve said...However, the vast-almost all-majority of propulsion engines are mounted on flexible,vibration dampening mounts, with or without an intermediate bearing and supports...in virtually all pleasurecraft and most small to medium commercial apps. .......But this is far more information than I think you were seeking...lol Good luck in whatever venture you decide to take on...Screw the NYYC types.... Best Regards, markvictor Mark, I take advantage of your expertise for a question I was never able to solve. In my 1973 sailboat (bought in 1991) the shaft line includes an "Aqua-drive like" twin universal joint piece and a standalone bearing/support/dripless-shaft-seal all in one piece (engine: Perkins 4.108 + VelvetDrive transm.). This last part has two or three (don't remember exactly) lip-seals on the water/stern side where the shaft enters, and a couple of big ball bearings (one radial and one axial) flooded in grease inside. No oil or water cooling. Shortly after buying the boat I had to dismantle the assembly and change the ball bearings, the lipseals and have the shaft rectified because there was water inside. Since then I just checked the grease once in a while and added some. My question is: what the heck is it since I cannot find any documentation? What kind of grease should I use? Every how many years should I check the lip-seals and the shaft? Thanks Daniel |
#13
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posted to rec.boats.building
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Daniel,
I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor |
#14
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posted to rec.boats.building
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..
Daniel, I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor http://groups.google.com/group/badboatbiz |
#15
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posted to rec.boats.building
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Daniel,
I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor http://groups.google.com/group/badboatbiz |
#16
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posted to rec.boats.building
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![]() Daniel, I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor |
#17
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posted to rec.boats.building
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![]() Daniel wrote: markvictor wrote: Hello again Thomas, Let's dispell some more myths...and agree with some truths. We already know thae all boats do NOT have struts, particularly full-keel sailboats as opposed to fin-keeled....Many boats of higher -end construction(Nordhaven comes to mind,for instance) have bearings at the inner and outer end of the shaft log to reduce load on the TAILSHAFT bearing of the gearbox or reduction gear and to prevent "whipping of the shaft" ( a jump-rope-like effect) often caused by a long unsupported length of shaft and some misalignment-it doesn't take much-...Most commercial craft DO have strut and cutlass bearings; I have replaced many more than I care to count, having been in the marine service industry for the last 27+ years... The ceramic "face seal" that Steve refers to is a PSS "dripless shaft seal, and I see them far more often in pleasure boats than in Commercial applications. More commercial boats who have oil cooled upper bearings or standard logs use a TIDES type dripless seal, a lipseal very similar to a grease seal, this must be cooled by oil (the minority)or raw water which is engine supplied if available or supplied by a static siphon vent in keel- cooled apps, and typically with lower shaft RPM's (under 2000) The oil cooled stuffing boxes are becoming increasingly scarce on all but ships, they are environmentally detrimental as they leak oil to seawater intentionally, the approved versions are completely lubricant-captive and are quite expensive.The stand alone bearing and support Steve speaks of(Aqua-Drive) and similar has a twofold purpose: it allows major shaft misalignment to facilitate a variety of engine installations and it transfers thust directly to the stringers as Steve said...However, the vast-almost all-majority of propulsion engines are mounted on flexible,vibration dampening mounts, with or without an intermediate bearing and supports...in virtually all pleasurecraft and most small to medium commercial apps. .......But this is far more information than I think you were seeking...lol Good luck in whatever venture you decide to take on...Screw the NYYC types.... Best Regards, markvictor Mark, I take advantage of your expertise for a question I was never able to solve. In my 1973 sailboat (bought in 1991) the shaft line includes an "Aqua-drive like" twin universal joint piece and a standalone bearing/support/dripless-shaft-seal all in one piece (engine: Perkins 4.108 + VelvetDrive transm.). This last part has two or three (don't remember exactly) lip-seals on the water/stern side where the shaft enters, and a couple of big ball bearings (one radial and one axial) flooded in grease inside. No oil or water cooling. Shortly after buying the boat I had to dismantle the assembly and change the ball bearings, the lipseals and have the shaft rectified because there was water inside. Since then I just checked the grease once in a while and added some. My question is: what the heck is it since I cannot find any documentation? What kind of grease should I use? Every how many years should I check the lip-seals and the shaft? Thanks Danie Daniel, I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor |
#18
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posted to rec.boats.building
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markvictor wrote:
Daniel, I think I know what you're talking about, but let's see...The seals,are they outboard of the ball bearing?(towards the water) In that configuration,they often run two seals facing in opposite directions, they call this a back to back configuration-one seal retains grease, the other repels water, This system still allows a small amount of water past the lip seal or it would burn up...the key here is to keep the grease topped off,to prevent excessive water fromthe bearing,the shaft really doesn't need to be checked unless you start to get water past your bearing which would indicate serios wear on the seals...A good MARINE grease such as lubriplate or equiv.is essential...It is usually a pale bluish green and has excellent water resistant qualities..You'll see how hard it is when you try to wash it from your hands,even with soap and water..Assuming you have a zerk fitting,one or two quick squirts from a grease gun every say, 5 or 6 hours of running time should be plenty...and remember that the intermediate bearing and thrust plate needs to be properly aligned with the propshaft to prevent the seals from premature failure...one thibg I'm not clear on is how your shaft was damaged...let me know so I can get a better take on what your original problem was all about...Also what model/make is your boat? Regards, markvictor Mark, yes I sort of remember the back-to-back seal configuration and yes, the seals were on the outer part of the assembly (towards the water). The damage consisted in wear where the lip-seals touched the shaft: very smooth annular groves matching exactly the seal position. Your suggestion of the kind of grease is very helpful and I will follow it. For a while I thought I had to use a liquid grease and let it flow; you know like a small container full of oil connected through a small hose and placed one foot above the system. But it "drank" a lot of oil and soon I disconnected the whole selfmade assembly and used thick lubricant again. Regarding the boat model/make, I am afraid it may be of little help as you will realize: the boat model is called "Orca", a 43' sloop designed by the US architect Dick Carter but completely built in Italy in 1973. The outstanding thing is that such a device is very unusual in sailboats of this kind and I have not found anybody familiar with it. I would like very much to find a mechanical drawing, specs and instructions but this seems an almost impossible deed. Anyway, thank you very much for your help, I appreciate very much your kindness. Daniele |
#19
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posted to rec.boats.building
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Hey Daniele...or is it Daniel?...
no matter...I've seen similar set-ups on Hallberg-Rasseys, including the lube resevoirs( on the rudder as well)...but I too have found them to ocassionally be problematic, and even the smallest flaw causes leaks...The fact that the grooves were caused by the seal bodies suggest that there may have been an alignment problem which caused the failure...so I would check or have it checked at your earliest convenience to prevent recurrance...One thing I might suggest if you have the room, next time you have it apart you can double up the "water out seal", if not ,check with a seal distributor, they have "double lip"seals available which effectively doubles the seals abilities...I.ll keep an eye out for some kind of drawing or print...if you go to my group (link below) you can e-mail me and I'll get in touch if I can find anything..... Regards, markvictor http://groups.google.com/group/badboatbiz |
#20
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posted to rec.boats.building
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I don't know if you have this info already, but perhaps it's a start..
Boats Outfitted L.o.a. Designer m Galatea, Mariver (4) 12.00 Sparkman & Stephens Optimist, Sailboats (4) 10.20 D. Carter Orca, Sailboats 12.00 D. Carter Vanessa 10.20 Van De Stadt Quasar 14.50 C. Sciarelli Pilussa 14.50 Sparkman & Stephens Sajano 16.00 M. Roberti Motorsailer, Franchini 14.00 R. Starkel Cayman 17.20 G. Frers Cantiere Nautico Morri & Para Via San Martino Riparotta 12 47049 Viserba di Rimini RN, Italy Fax: +39-0541-740593 · Tel: +39-0541-740593 Perhaps they can provide you with some documentation or steer you in the right direction.... Regards, markvictor http://groups.google.com/group/badboatbiz?hl=en |
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