Dripless

[Ken Coit]

I understand the rationale for wanting a dry engine sump, but I don't understand why one would add an expensive component with several additional failure modes when any failure could sink the boat. With all these vent hose support wires spinning around in the bilge, who in the world would want a rubber or other flexible hose exposed? As I understand it, if the hose fails, the boat sinks.

How do insurance companies feel about this? Do they know about it? Do they require that the units be replaced per the manufacturer's recommendations? The life of the Spartan stuffing box seems fairly long, we are going on 18 years; I beleive the dripless units need to be replaced every so often. Do we have any experience with that? The guarantee is only 3 years, does it cover the boat or simply repair or replacement?

Too many questions for me; I'll stick with simple and inexpensive for now.

Keep on sailing,

Ken Coit
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC



[img]http://www.shaftseal.com/pictures/psssh ... ftseal.jpg[/img]
parfaitNOSPAM@nc.rr.com

[Tom]

There's dripless packings and then there's dripless packings. The PSS version that you're referring to recommends that the bellows hose be changed every three years, but the surface doesn't wear out in 3 years. The bellows hose is pretty lightweight in my opinion and was one of the reasons I didn't go that way. The tension between the two surfaces depends upon the bellows hose having pressure against the surface. As the hose ages and loses its tension it seems to me you lose the pressure between those two surfaces. Now if you're a meticulous person and really do change the bellows hose every third year maybe it would be OK and in truth I haven't heard of anybody having trouble with that, but I didn't want to pull my prop shaft and crawl in the bilge every third year to change out that hose. BTW hoses aren't free either. Another thing I didn't like was the vulnerability of the surfaces to any kind of contaminant such as barnacle shells. Once you get that surface scratched and lose the polish it won't seal any longer.

I went the way De Mers and many others on this board went, which is to say, use the same old stuffing box the boat came with, but replace some of the rings of oakem with the new teflon packing. This gives you the best of both worlds, i.e., you have a dripless stuffing box that is rugged and can be adjusted as it wears, and you don't have to replace the hose every three years to maintain your watertight integrity. If you get the 6 or 8 ply hose that is specially made for stuffing boxes you should be good for 20 or 30 years. It's not that easy to find anymore, but you only have to deal with it every 20 years or so. By comparison the bellows hoses are so thin walled they scare me and they flex all the time. BTW the vent hoses usually have a zip tie around them and are screwed to the fore and aft bulkhead so they can't get over to the prop shaft to get tangled. While you're in there changing your bellows hose every three years check to make sure your vent hoses are still fastened securely and the zip ties haven't broken off.

Just my opinion, but these things always start a debate! So lay on, MacDuff, and damned be he who first cries, "Hold enough!"

I understand the rationale for wanting a dry engine sump, but I don't understand why one would add an expensive component with several additional failure modes when any failure could sink the boat. With all these vent hose support wires spinning around in the bilge, who in the world would want a rubber or other flexible hose exposed? As I understand it, if the hose fails, the boat sinks.

How do insurance companies feel about this? Do they know about it? Do they require that the units be replaced per the manufacturer's recommendations? The life of the Spartan stuffing box seems fairly long, we are going on 18 years; I beleive the dripless units need to be replaced every so often. Do we have any experience with that? The guarantee is only 3 years, does it cover the boat or simply repair or replacement?

Too many questions for me; I'll stick with simple and inexpensive for now.

Keep on sailing,

Ken Coit
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC

TomCambria@mindspring.com

[John R.]

Guys,

FYI there are two different types of bellows hose for dripless shaft seals like the Lasdrop, PSS, et al. There is a standard version which is a non reinforced nitrile type rubber that is pretty tough and is specifically used on low rpm engines like small diesels and then there are heavily reinforced laminated bellows hoses for heavy duty high rpm application use. These things are as tough if not tougher than standard shaftlog hoses.

Tom is certainly correct about the seal faces not wearing out. The problems occur when the seal faces are damaged by mishandling when installing or later servicing. My Lasdrop seal has been in the boat for at least ten years now and I have had no problems with it. I did originally install the optional heavily reinforced bellows. I currently prefer the PSS shaft seal but haven't seen the new generation Lasdrop for comparison.

I have seen a few traditional shaftlog hoses that attach stuffing boxes to shaft logs which have had leakage problems over the years and so I believe none of these shaft seal systems are perfect and without risk. Generally speaking from my experiences it is without a doubt more maintenance and more difficult maintenance to have a traditional stuffing box than a dripless seal.

With the heavy duty bellows hose I've never noticed any appreciable loss in flexibility in the hose. The tension pressure can easily be adjusted by simply adding a little more compression to the bellows. The bellows hose would have to be in absolutely deplorable condition to be so deteriorated as to not be able to apply sufficient pressure against the sealing faces to not create a good seal. It doesn't require much tension to mate the seal faces. The key to a good seal with these units is to properly align and mount the bellows hose to the stern tube in the first place, that is a very important step. When there are seal problems that's what is usually the cause of problem. I can say that I have ever seen one of these seals have a bellows hose problem.

Tom, I don't understand the comments about the vulnerability of the surfaces to contaminants such as "barnacle shells". They (barnacle shells) simply can't get to the seal face. The only thing that I have ever seen that has caused a problem with a seal face is physical damage caused during installation such as a deep scratch or heavy nick due to careless handling.

Dripless seals and teflon packing both have advantages and disadvantages. They both rely on a stern tube hose for seal integrity. They both are vulnerable to neglect and lack of maintenance. The dripless seals are easier to deal with from my experiences. More and more manufacturers seem to be using dripless seals every year.

As for the insurance issues posed, my insurance is through West marine and they are well aware the boat has a dripless shaft seal and I have never heard a word of concern about it from them. It is even stipulated clearly in the boats preinsurance survey report she is equipped with a dripless shaft seal.

These are just a few counter views on the dripless seal by a user and a past dealer. We all know full well there are disaster stories surrounding any shaft seal type. It's usually not the seals but the owners or mechanics that are the root of the problem in those disaster situations.

There's dripless packings and then there's dripless packings. The PSS version that you're referring to recommends that the bellows hose be changed every three years, but the surface doesn't wear out in 3 years. The bellows hose is pretty lightweight in my opinion and was one of the reasons I didn't go that way. The tension between the two surfaces depends upon the bellows hose having pressure against the surface. As the hose ages and loses its tension it seems to me you lose the pressure between those two surfaces. Now if you're a meticulous person and really do change the bellows hose every third year maybe it would be OK and in truth I haven't heard of anybody having trouble with that, but I didn't want to pull my prop shaft and crawl in the bilge every third year to change out that hose. BTW hoses aren't free either. Another thing I didn't like was the vulnerability of the surfaces to any kind of contaminant such as barnacle shells. Once you get that surface scratched and lose the polish it won't seal any longer.

I went the way De Mers and many others on this board went, which is to say, use the same old stuffing box the boat came with, but replace some of the rings of oakem with the new teflon packing. This gives you the best of both worlds, i.e., you have a dripless stuffing box that is rugged and can be adjusted as it wears, and you don't have to replace the hose every three years to maintain your watertight integrity. If you get the 6 or 8 ply hose that is specially made for stuffing boxes you should be good for 20 or 30 years. It's not that easy to find anymore, but you only have to deal with it every 20 years or so. By comparison the bellows hoses are so thin walled they scare me and they flex all the time. BTW the vent hoses usually have a zip tie around them and are screwed to the fore and aft bulkhead so they can't get over to the prop shaft to get tangled. While you're in there changing your bellows hose every three years check to make sure your vent hoses are still fastened securely and the zip ties haven't broken off.

Just my opinion, but these things always start a debate! So lay on, MacDuff, and damned be he who first cries, "Hold enough!"

I understand the rationale for wanting a dry engine sump, but I don't understand why one would add an expensive component with several additional failure modes when any failure could sink the boat. With all these vent hose support wires spinning around in the bilge, who in the world would want a rubber or other flexible hose exposed? As I understand it, if the hose fails, the boat sinks.

How do insurance companies feel about this? Do they know about it? Do they require that the units be replaced per the manufacturer's recommendations? The life of the Spartan stuffing box seems fairly long, we are going on 18 years; I beleive the dripless units need to be replaced every so often. Do we have any experience with that? The guarantee is only 3 years, does it cover the boat or simply repair or replacement?

Too many questions for me; I'll stick with simple and inexpensive for now.

Keep on sailing,

Ken Coit
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC

[Tom]

<then there are heavily
reinforced laminated bellows hoses for heavy duty high rpm application use.>

I was unaware that there is a heavier gauge bellows hose. That is certainly a plus. Would the avereage guy going in to buy one know that there is a heavier hose available? Wouldn't he look at the information and see that he has a low speed diesel and therefore assume that he should order that hose for his boat? If the nitrile bellows hose is pretty tough, why does the factory itself recommend replacing them every three years? Congruently, does the fact that you put a heavy duty hose on your boat mean that you didn't trust the lightweight hose either, or do you have a high speed engine that requires it? Are you suggesting that everyone should use the heavier duty hose even with low speed diesels?

As far as the barnacle and etc comment goes, I kept my boat in a marina that is very shallow and less than 3 feet deep on a minus tide. It's on a muddy slough and many times you'd be coming in with only 6 inches between the bottom of the keel and the ocean bottom. In very shallow water like that the load of silt in the water eats impellers on raw water pumps, so I just figured without any real evidence that it might get on the surfaces of the PSS shaft seal and cause scratches or whatever there. Maybe that was an unfounded fear. Perhaps the PSS seals so tightly that no water ever gets between the two surfaces.

-When there are seal problems that's what is usually the cause...- (i.e., mis-alignment)

This seems to be saying that you have in fact seen seal problems with those units, but you put it down to user error in every case.

Innsurance companies being what they are, if your boat sank due to a shaft seal problem and they discovered that you hadn't replaced the bellows hose in the last three years per the manufacturer's instructions couldn't they weasel out of paying by saying that it was owner error that sank the boat? I doubt if they would accept the argument that you were using heavier hose and therefore it wasn't necessary to change that often. They might even ding you for not using the manufacturer's recommended hose.

I don't have any strong feelings against the PSS system and have no personal experience of anyone having a problem. After looking at the alternatives it's not the way I chose to go is all. I don't say I'm right, I'm just laying out my thinking of the subject to be refuted or considered. I think these kinds of discussions are good because people who installed a PSS system may have forgotten that they are supposed to change the hose every three years and will now go check it. People who went with teflon may wonder if theirs is still drip free or needs adjustment. In fact I haven't checked mine in some time and this reminds me I have to do that next week.

Don't you love a good debate, MacDuff?

Guys,

FYI there are two different types of bellows hose for dripless shaft seals like the Lasdrop, PSS, et al. There is a standard version which is a non reinforced nitrile type rubber that is pretty tough and is specifically used on low rpm engines like small diesels and then there are heavily reinforced laminated bellows hoses for heavy duty high rpm application use. These things are as tough if not tougher than standard shaftlog hoses.

Tom is certainly correct about the seal faces not wearing out. The problems occur when the seal faces are damaged by mishandling when installing or later servicing. My Lasdrop seal has been in the boat for at least ten years now and I have had no problems with it. I did originally install the optional heavily reinforced bellows. I currently prefer the PSS shaft seal but haven't seen the new generation Lasdrop for comparison.

I have seen a few traditional shaftlog hoses that attach stuffing boxes to shaft logs which have had leakage problems over the years and so I believe none of these shaft seal systems are perfect and without risk. Generally speaking from my experiences it is without a doubt more maintenance and more difficult maintenance to have a traditional stuffing box than a dripless seal.

With the heavy duty bellows hose I've never noticed any appreciable loss in flexibility in the hose. The tension pressure can easily be adjusted by simply adding a little more compression to the bellows. The bellows hose would have to be in absolutely deplorable condition to be so deteriorated as to not be able to apply sufficient pressure against the sealing faces to not create a good seal. It doesn't require much tension to mate the seal faces. The key to a good seal with these units is to properly align and mount the bellows hose to the stern tube in the first place, that is a very important step. When there are seal problems that's what is usually the cause of problem. I can say that I have ever seen one of these seals have a bellows hose problem.

Tom, I don't understand the comments about the vulnerability of the surfaces to contaminants such as "barnacle shells". They (barnacle shells) simply can't get to the seal face. The only thing that I have ever seen that has caused a problem with a seal face is physical damage caused during installation such as a deep scratch or heavy nick due to careless handling.

Dripless seals and teflon packing both have advantages and disadvantages. They both rely on a stern tube hose for seal integrity. They both are vulnerable to neglect and lack of maintenance. The dripless seals are easier to deal with from my experiences. More and more manufacturers seem to be using dripless seals every year.

As for the insurance issues posed, my insurance is through West marine and they are well aware the boat has a dripless shaft seal and I have never heard a word of concern about it from them. It is even stipulated clearly in the boats preinsurance survey report she is equipped with a dripless shaft seal.

These are just a few counter views on the dripless seal by a user and a past dealer. We all know full well there are disaster stories surrounding any shaft seal type. It's usually not the seals but the owners or mechanics that are the root of the problem in those disaster situations.

There's dripless packings and then there's dripless packings. The PSS version that you're referring to recommends that the bellows hose be changed every three years, but the surface doesn't wear out in 3 years. The bellows hose is pretty lightweight in my opinion and was one of the reasons I didn't go that way. The tension between the two surfaces depends upon the bellows hose having pressure against the surface. As the hose ages and loses its tension it seems to me you lose the pressure between those two surfaces. Now if you're a meticulous person and really do change the bellows hose every third year maybe it would be OK and in truth I haven't heard of anybody having trouble with that, but I didn't want to pull my prop shaft and crawl in the bilge every third year to change out that hose. BTW hoses aren't free either. Another thing I didn't like was the vulnerability of the surfaces to any kind of contaminant such as barnacle shells. Once you get that surface scratched and lose the polish it won't seal any longer.

I went the way De Mers and many others on this board went, which is to say, use the same old stuffing box the boat came with, but replace some of the rings of oakem with the new teflon packing. This gives you the best of both worlds, i.e., you have a dripless stuffing box that is rugged and can be adjusted as it wears, and you don't have to replace the hose every three years to maintain your watertight integrity. If you get the 6 or 8 ply hose that is specially made for stuffing boxes you should be good for 20 or 30 years. It's not that easy to find anymore, but you only have to deal with it every 20 years or so. By comparison the bellows hoses are so thin walled they scare me and they flex all the time. BTW the vent hoses usually have a zip tie around them and are screwed to the fore and aft bulkhead so they can't get over to the prop shaft to get tangled. While you're in there changing your bellows hose every three years check to make sure your vent hoses are still fastened securely and the zip ties haven't broken off.

Just my opinion, but these things always start a debate! So lay on, MacDuff, and damned be he who first cries, "Hold enough!"

I understand the rationale for wanting a dry engine sump, but I don't understand why one would add an expensive component with several additional failure modes when any failure could sink the boat. With all these vent hose support wires spinning around in the bilge, who in the world would want a rubber or other flexible hose exposed? As I understand it, if the hose fails, the boat sinks.

How do insurance companies feel about this? Do they know about it? Do they require that the units be replaced per the manufacturer's recommendations? The life of the Spartan stuffing box seems fairly long, we are going on 18 years; I beleive the dripless units need to be replaced every so often. Do we have any experience with that? The guarantee is only 3 years, does it cover the boat or simply repair or replacement?

Too many questions for me; I'll stick with simple and inexpensive for now.

Keep on sailing,

Ken Coit
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC

TomCambria@mindspring.com

[Warren Kaplan]

This is my second year with a PSS Shaft Seal. So far, so good. I bought the High Speed shaft seal instead of the standard low speed seal that is standard for a sailboat. I think 12 knot boat speed is the cut off. Why did I do it, you ask? First, the bellows I believe is more rugged. Second, the high speed seal has water pumped into the seal for "lubrication" while the standard seal has a passive water setup. Not pumped in. On the high speed seal a small hose is installed from the exhaust water, near the mixing elbow, and some of that water is just pumped through that hose into the seal instead of all of the water just going out the exhaust. There is no extra pump to worry about. So you can be sure the seal is getting adequate cooling water and lubrication on the active High Speed Seal. I think the difference in price for the CD27 size seal was maybe $50. Well worth it for the piece of mind. The only other concern with a PSS is winterization up north. I called them about it. They told me that you don't want to get any foreign material on the faces of the integral parts because that could cause some problems so they told me to disconnect the exhaust water connection to the seal when pumping antifreeze thru the engine before winter layup. I just run about 5 gallons of fresh water thru the whole engine/seal system to get the salt out. Then I disconnect the seal hose and start to pump the antifreeze thru. Finished. Come spring, I reverse. I flush the engine with fresh water to get all the antifreeze out. Then connect the shaft seal hose from the exhaust and we're in business. The spring ritual isn't so important because if you run the engine, even with the winter antifreeze in, the raw water will flush everything out anyway, even if it goes thru the shaft seal for 30 seconds. Bilge stays dry and as I said, I'm happy with it so far.

Warren Kaplan
Sine Qua Non
CD27
Oyster Bay Harbor, NY



Setsail728@aol.com

[Robert Pierce]

I have been using GFO Fiber dripless packing by Gore. I have had no problems with it and it intalls the same as the standard packing. It is also inexpensive.



Robert-Pierce@attbi.com

[John Nuttall]

......from the engine? To filter out any chunks of corrosion, say from the engine or exchanger? If a large enough particle passed thru, could damage the seals.......???

Or maybe I am just envisioning this arrangement wrong......having never seen one... ;-]

Ken you got a picture of an installation?
John

[Tom]

So if you're sailing in silty water you're pumping silt onto the surfaces that are supposed to seal? That sounds like the low speed one would be safer to use in any but clean water. There's no witerizing issue with teflon.

This is my second year with a PSS Shaft Seal. So far, so good. I bought the High Speed shaft seal instead of the standard low speed seal that is standard for a sailboat. I think 12 knot boat speed is the cut off. Why did I do it, you ask? First, the bellows I believe is more rugged. Second, the high speed seal has water pumped into the seal for "lubrication" while the standard seal has a passive water setup. Not pumped in. On the high speed seal a small hose is installed from the exhaust water, near the mixing elbow, and some of that water is just pumped through that hose into the seal instead of all of the water just going out the exhaust. There is no extra pump to worry about. So you can be sure the seal is getting adequate cooling water and lubrication on the active High Speed Seal. I think the difference in price for the CD27 size seal was maybe $50. Well worth it for the piece of mind. The only other concern with a PSS is winterization up north. I called them about it. They told me that you don't want to get any foreign material on the faces of the integral parts because that could cause some problems so they told me to disconnect the exhaust water connection to the seal when pumping antifreeze thru the engine before winter layup. I just run about 5 gallons of fresh water thru the whole engine/seal system to get the salt out. Then I disconnect the seal hose and start to pump the antifreeze thru. Finished. Come spring, I reverse. I flush the engine with fresh water to get all the antifreeze out. Then connect the shaft seal hose from the exhaust and we're in business. The spring ritual isn't so important because if you run the engine, even with the winter antifreeze in, the raw water will flush everything out anyway, even if it goes thru the shaft seal for 30 seconds. Bilge stays dry and as I said, I'm happy with it so far.

Warren Kaplan
Sine Qua Non
CD27
Oyster Bay Harbor, NY

TomCambria@mindspring.com

[John R.]

Yeah, This is a good discussion. Lot's of good thinking going on.

I think (although my writing skills are in question) that I may be able to help people understand how these seals work. First of all no water goes between the sealing surfaces as is assumed based on some of the comments that have been expressed. Take my Lasdrop for example, it seals on a beveled edge. The plastic teflon section (which clamps into the end of the compression bellows stern tube hose)has a finely beveled edge that rides against a larger beveled edge which is machined onto the other piece of the seal which is the fixed (clamped to the shaft) stainless ring. The beveled edge of that stainless section rides against the narrow beveled edge of the teflon piece, it actually penetrates the teflon section somewhat. That allows the bellows hose and teflon piece to be able to move or vibrate and not cause any leakage. If the two pieces of the seal are off axis to one another it will still seal. The only way leakage will occur is if you manually grab the bellows hose and push it back pulling the seal halves apart. Plenty of pressure is kept against the mating seal halves by the bellows hose,even the standard rubber one which is much stiffer than it looks. The high speed fabric reinforced hose is even stiffer. The best thing to do is look at them in person. They are quite good units and well designed. They aren't some piece of junk some guy threw together in his shed. It's good marine gear but an owner has to follow proper installation methods just like he would with a traditional stuffing box. As we all well know they have vulnerabilities also.

Tom, I don't know if teh average owner would be aware of the difference in hoses between the low rpm unit and the high rpm unit. That is up to the owner and the place where he shops for it. If a person were interested in a piece of gear like these shaft seals they should contact the manufacturer and pose their technical questions rather than depend on an average salesperson in a store. This type of gear is important and a prudent owner will do proper homework before laying down a penny when the security of his boat is at stake.

The reason why I chose to install the heavy duty fabric reinforced hose was because I thought it added more security even though it wasn't considered necessary by the manufacturer on a small diesel. I always recommended the heavy bellows to customers. Some went with it and some didn't. No one that I am aware of to this day has had any problems with either hose. The cost is obviously higher on the heavy duty bellows hose.

When I sold shaft seals there was no recommendation to change hoses every three years. I'm not sure who may be recommending that practice at this time. My unit still has the original hose and there is no reason to change it as it still places plenty of pressure against the sealing faces. I suppose if a hose was weaked or damaged by rusting clamps then changing the hose would be necessary just as it would be with a traditional stern tube hose on a flax stuffing box.

Yes, I would recommend everyone use the heavy duty bellows hose even on a small diesel. I prefer to be on the cautious side when it is possible and at reasonable cost.

The silt you describe would not contact the sealing faces, no water will unless the seal is pushed apart by someone. No water gets between the seal faces once it has broken in after a new installation and the surfaces have mated to each other (about an hours running time). Water that feeds up through the boats stern tube cools the seal but does not lubricate it. It does not function like a traditional flax stuffing box.

Yes, I have seen some seepage from some units or even a spray when the shaft was running. I can recall two cases inparticular. After dismantling the units for customers it was discovered the teflon sections had damage to their sealing faces. These were imperfections on the perfectly smooth flawless face that were caused by rough handling and lack of skill during installation.


If a boat sinks because of a hose not being changed on a dripless shaft seal I truly don't believe it would be any kind of issue with an insurance company. First of all I don't think they would have a clue about the scheduled hose change interval you mentioned. Secondly boats sink for far more stupid and incompetent reasons and they still pay their insured. That's why they are in the risk business and poor slobs like us pay the tab in our premiums to cover the incompetence and caused claims by those who are careless with their boats. I live in the hurricane belt, very few boats are properly prepared by owners but when there is damage they all still get paid. That's the risk business for you! Maybe someone that reads this board that's in the insurance business can give you a professional perspective on claim criteria.

There are several different types of shaft seals on the market, traditional stuffing boxes, dripless shaft seals, lip seals, oil seals, and others. They all have their pros and cons and associated risks. Every person has to decide for themselves what they are comfortable with and can afford to purchase or maintain. Think about seacocks and thru hulls, there are different types and different opinions on them as well. Nothing is cast in stone on this stuff.

<then there are heavily
reinforced laminated bellows hoses for heavy duty high rpm application use.>

I was unaware that there is a heavier gauge bellows hose. That is certainly a plus. Would the avereage guy going in to buy one know that there is a heavier hose available? Wouldn't he look at the information and see that he has a low speed diesel and therefore assume that he should order that hose for his boat? If the nitrile bellows hose is pretty tough, why does the factory itself recommend replacing them every three years? Congruently, does the fact that you put a heavy duty hose on your boat mean that you didn't trust the lightweight hose either, or do you have a high speed engine that requires it? Are you suggesting that everyone should use the heavier duty hose even with low speed diesels?

As far as the barnacle and etc comment goes, I kept my boat in a marina that is very shallow and less than 3 feet deep on a minus tide. It's on a muddy slough and many times you'd be coming in with only 6 inches between the bottom of the keel and the ocean bottom. In very shallow water like that the load of silt in the water eats impellers on raw water pumps, so I just figured without any real evidence that it might get on the surfaces of the PSS shaft seal and cause scratches or whatever there. Maybe that was an unfounded fear. Perhaps the PSS seals so tightly that no water ever gets between the two surfaces.

-When there are seal problems that's what is usually the cause...- (i.e., mis-alignment)

This seems to be saying that you have in fact seen seal problems with those units, but you put it down to user error in every case.

Innsurance companies being what they are, if your boat sank due to a shaft seal problem and they discovered that you hadn't replaced the bellows hose in the last three years per the manufacturer's instructions couldn't they weasel out of paying by saying that it was owner error that sank the boat? I doubt if they would accept the argument that you were using heavier hose and therefore it wasn't necessary to change that often. They might even ding you for not using the manufacturer's recommended hose.

I don't have any strong feelings against the PSS system and have no personal experience of anyone having a problem. After looking at the alternatives it's not the way I chose to go is all. I don't say I'm right, I'm just laying out my thinking of the subject to be refuted or considered. I think these kinds of discussions are good because people who installed a PSS system may have forgotten that they are supposed to change the hose every three years and will now go check it. People who went with teflon may wonder if theirs is still drip free or needs adjustment. In fact I haven't checked mine in some time and this reminds me I have to do that next week.

Don't you love a good debate, MacDuff?

Guys,

FYI there are two different types of bellows hose for dripless shaft seals like the Lasdrop, PSS, et al. There is a standard version which is a non reinforced nitrile type rubber that is pretty tough and is specifically used on low rpm engines like small diesels and then there are heavily reinforced laminated bellows hoses for heavy duty high rpm application use. These things are as tough if not tougher than standard shaftlog hoses.

Tom is certainly correct about the seal faces not wearing out. The problems occur when the seal faces are damaged by mishandling when installing or later servicing. My Lasdrop seal has been in the boat for at least ten years now and I have had no problems with it. I did originally install the optional heavily reinforced bellows. I currently prefer the PSS shaft seal but haven't seen the new generation Lasdrop for comparison.

I have seen a few traditional shaftlog hoses that attach stuffing boxes to shaft logs which have had leakage problems over the years and so I believe none of these shaft seal systems are perfect and without risk. Generally speaking from my experiences it is without a doubt more maintenance and more difficult maintenance to have a traditional stuffing box than a dripless seal.

With the heavy duty bellows hose I've never noticed any appreciable loss in flexibility in the hose. The tension pressure can easily be adjusted by simply adding a little more compression to the bellows. The bellows hose would have to be in absolutely deplorable condition to be so deteriorated as to not be able to apply sufficient pressure against the sealing faces to not create a good seal. It doesn't require much tension to mate the seal faces. The key to a good seal with these units is to properly align and mount the bellows hose to the stern tube in the first place, that is a very important step. When there are seal problems that's what is usually the cause of problem. I can say that I have ever seen one of these seals have a bellows hose problem.

Tom, I don't understand the comments about the vulnerability of the surfaces to contaminants such as "barnacle shells". They (barnacle shells) simply can't get to the seal face. The only thing that I have ever seen that has caused a problem with a seal face is physical damage caused during installation such as a deep scratch or heavy nick due to careless handling.

Dripless seals and teflon packing both have advantages and disadvantages. They both rely on a stern tube hose for seal integrity. They both are vulnerable to neglect and lack of maintenance. The dripless seals are easier to deal with from my experiences. More and more manufacturers seem to be using dripless seals every year.

As for the insurance issues posed, my insurance is through West marine and they are well aware the boat has a dripless shaft seal and I have never heard a word of concern about it from them. It is even stipulated clearly in the boats preinsurance survey report she is equipped with a dripless shaft seal.

These are just a few counter views on the dripless seal by a user and a past dealer. We all know full well there are disaster stories surrounding any shaft seal type. It's usually not the seals but the owners or mechanics that are the root of the problem in those disaster situations.

There's dripless packings and then there's dripless packings. The PSS version that you're referring to recommends that the bellows hose be changed every three years, but the surface doesn't wear out in 3 years. The bellows hose is pretty lightweight in my opinion and was one of the reasons I didn't go that way. The tension between the two surfaces depends upon the bellows hose having pressure against the surface. As the hose ages and loses its tension it seems to me you lose the pressure between those two surfaces. Now if you're a meticulous person and really do change the bellows hose every third year maybe it would be OK and in truth I haven't heard of anybody having trouble with that, but I didn't want to pull my prop shaft and crawl in the bilge every third year to change out that hose. BTW hoses aren't free either. Another thing I didn't like was the vulnerability of the surfaces to any kind of contaminant such as barnacle shells. Once you get that surface scratched and lose the polish it won't seal any longer.

I went the way De Mers and many others on this board went, which is to say, use the same old stuffing box the boat came with, but replace some of the rings of oakem with the new teflon packing. This gives you the best of both worlds, i.e., you have a dripless stuffing box that is rugged and can be adjusted as it wears, and you don't have to replace the hose every three years to maintain your watertight integrity. If you get the 6 or 8 ply hose that is specially made for stuffing boxes you should be good for 20 or 30 years. It's not that easy to find anymore, but you only have to deal with it every 20 years or so. By comparison the bellows hoses are so thin walled they scare me and they flex all the time. BTW the vent hoses usually have a zip tie around them and are screwed to the fore and aft bulkhead so they can't get over to the prop shaft to get tangled. While you're in there changing your bellows hose every three years check to make sure your vent hoses are still fastened securely and the zip ties haven't broken off.

Just my opinion, but these things always start a debate! So lay on, MacDuff, and damned be he who first cries, "Hold enough!"

[Warren Kaplan]

......from the engine? To filter out any chunks of corrosion, say from the engine or exchanger? If a large enough particle passed thru, could damage the seals.......???

Or maybe I am just envisioning this arrangement wrong......having never seen one... ;-]

Ken you got a picture of an installation?
John

John,
No filter in the line from the exhaust water connection to the shaft seal. Take a look at the link below or give them a call if you have questions. Or e-mail. They were very helpful to me.

Warren Kaplan
Sine Qua Non
CD27
Oyster Bay Harbor, NY



Setsail728@aol.com

[John R.]

Warren,

I find it very interesting that these days the manufacturers are apparently telling you to connect the hose barb on the high speed seal to an exhaust cooling water connection. The whole purpose of that barb in years past was to evacuate air that gets trapped within the stern tube after launching and during use especially with high speed craft using high rpm engines. The way the barbs used to be used was to mount the seal with the barb facing vertically and then attach a length of reinforced water hose and run that hose as far above the waterline as possible and turn the upper end in an inverted * U * position and secure it to the boat so it doesn't come loose. Then a piece of fine screen or mesh would be attached to the open end to prevent debris or insects from getting into the hose and clogging it. John Nuttal mentioned the issue of exhaust debris possibly entering the barbed fitting if the line is connected to a exhaust water fitting and I totally agree with his observation, I don't think that is a good idea and it isn't even necessary with the carbon seal used in the current model PSS seal because cooling isn't a factor. The only apparent need for the barbed fitting with a PSS seal would be to evacuate trapped air that accumulates especially with high speed craft. The whole purpose of doing the vent the way I previously described above was to facilitate water cooling the non carbon based seals and to evacuate the trapped air.

......from the engine? To filter out any chunks of corrosion, say from the engine or exchanger? If a large enough particle passed thru, could damage the seals.......???

Or maybe I am just envisioning this arrangement wrong......having never seen one... ;-]

Ken you got a picture of an installation?
John

John,
No filter in the line from the exhaust water connection to the shaft seal. Take a look at the link below or give them a call if you have questions. Or e-mail. They were very helpful to me.

Warren Kaplan
Sine Qua Non
CD27
Oyster Bay Harbor, NY

[Tom]

I don't see anyting wrong with your explanaiton or debating skills at all. Your discussion here has made me feel better about that style of seal. I don't recall the PSS seal having a beveled edge. Perhaps that was an later improvement or something unique to Lasdrop. I actually bought a PSS and was about to install it when someone raised many of the issues I raised here to me and scared me out of it. That's mainly why I switched to the teflon style. I still have that PSS unit in the garage somewhere unused and in the original box, and if I can find it, I'll pull it out and have another look at it and the directions.

As far as insurance companies go, perhaps you've had better luck with them than I have. I've never submitted a claim on my boat but I've had a lot of negative experience with car claims. (Where I was the victim not the perpetrator) A hurricane is considered an act of God and thus out of the control of the owner, but I have seem some of them try to weasel out of claims by claiming the problem was owner induced. I'm sure some of them are better than others. I've seen a lot of people try to defraud insurance companies too. But that's a subject for another bulletin board somewhere else.

I any case I've learned a lot from this discussion and I'm sure others have also. One of the great things about this BB is this type of discussion. Thanks for taking the time for such a detailed post. Regards, and as Ken, who started this thread, always says, Keep on Sailing.

Yeah, This is a good discussion. Lot's of good thinking going on.

I think (although my writing skills are in question) that I may be able to help people understand how these seals work. First of all no water goes between the sealing surfaces as is assumed based on some of the comments that have been expressed. Take my Lasdrop for example, it seals on a beveled edge. The plastic teflon section (which clamps into the end of the compression bellows stern tube hose)has a finely beveled edge that rides against a larger beveled edge which is machined onto the other piece of the seal which is the fixed (clamped to the shaft) stainless ring. The beveled edge of that stainless section rides against the narrow beveled edge of the teflon piece, it actually penetrates the teflon section somewhat. That allows the bellows hose and teflon piece to be able to move or vibrate and not cause any leakage. If the two pieces of the seal are off axis to one another it will still seal. The only way leakage will occur is if you manually grab the bellows hose and push it back pulling the seal halves apart. Plenty of pressure is kept against the mating seal halves by the bellows hose,even the standard rubber one which is much stiffer than it looks. The high speed fabric reinforced hose is even stiffer. The best thing to do is look at them in person. They are quite good units and well designed. They aren't some piece of junk some guy threw together in his shed. It's good marine gear but an owner has to follow proper installation methods just like he would with a traditional stuffing box. As we all well know they have vulnerabilities also.

Tom, I don't know if teh average owner would be aware of the difference in hoses between the low rpm unit and the high rpm unit. That is up to the owner and the place where he shops for it. If a person were interested in a piece of gear like these shaft seals they should contact the manufacturer and pose their technical questions rather than depend on an average salesperson in a store. This type of gear is important and a prudent owner will do proper homework before laying down a penny when the security of his boat is at stake.

The reason why I chose to install the heavy duty fabric reinforced hose was because I thought it added more security even though it wasn't considered necessary by the manufacturer on a small diesel. I always recommended the heavy bellows to customers. Some went with it and some didn't. No one that I am aware of to this day has had any problems with either hose. The cost is obviously higher on the heavy duty bellows hose.

When I sold shaft seals there was no recommendation to change hoses every three years. I'm not sure who may be recommending that practice at this time. My unit still has the original hose and there is no reason to change it as it still places plenty of pressure against the sealing faces. I suppose if a hose was weaked or damaged by rusting clamps then changing the hose would be necessary just as it would be with a traditional stern tube hose on a flax stuffing box.

Yes, I would recommend everyone use the heavy duty bellows hose even on a small diesel. I prefer to be on the cautious side when it is possible and at reasonable cost.

The silt you describe would not contact the sealing faces, no water will unless the seal is pushed apart by someone. No water gets between the seal faces once it has broken in after a new installation and the surfaces have mated to each other (about an hours running time). Water that feeds up through the boats stern tube cools the seal but does not lubricate it. It does not function like a traditional flax stuffing box.

Yes, I have seen some seepage from some units or even a spray when the shaft was running. I can recall two cases inparticular. After dismantling the units for customers it was discovered the teflon sections had damage to their sealing faces. These were imperfections on the perfectly smooth flawless face that were caused by rough handling and lack of skill during installation.


If a boat sinks because of a hose not being changed on a dripless shaft seal I truly don't believe it would be any kind of issue with an insurance company. First of all I don't think they would have a clue about the scheduled hose change interval you mentioned. Secondly boats sink for far more stupid and incompetent reasons and they still pay their insured. That's why they are in the risk business and poor slobs like us pay the tab in our premiums to cover the incompetence and caused claims by those who are careless with their boats. I live in the hurricane belt, very few boats are properly prepared by owners but when there is damage they all still get paid. That's the risk business for you! Maybe someone that reads this board that's in the insurance business can give you a professional perspective on claim criteria.

There are several different types of shaft seals on the market, traditional stuffing boxes, dripless shaft seals, lip seals, oil seals, and others. They all have their pros and cons and associated risks. Every person has to decide for themselves what they are comfortable with and can afford to purchase or maintain. Think about seacocks and thru hulls, there are different types and different opinions on them as well. Nothing is cast in stone on this stuff.

<then there are heavily
reinforced laminated bellows hoses for heavy duty high rpm application use.>

I was unaware that there is a heavier gauge bellows hose. That is certainly a plus. Would the avereage guy going in to buy one know that there is a heavier hose available? Wouldn't he look at the information and see that he has a low speed diesel and therefore assume that he should order that hose for his boat? If the nitrile bellows hose is pretty tough, why does the factory itself recommend replacing them every three years? Congruently, does the fact that you put a heavy duty hose on your boat mean that you didn't trust the lightweight hose either, or do you have a high speed engine that requires it? Are you suggesting that everyone should use the heavier duty hose even with low speed diesels?

As far as the barnacle and etc comment goes, I kept my boat in a marina that is very shallow and less than 3 feet deep on a minus tide. It's on a muddy slough and many times you'd be coming in with only 6 inches between the bottom of the keel and the ocean bottom. In very shallow water like that the load of silt in the water eats impellers on raw water pumps, so I just figured without any real evidence that it might get on the surfaces of the PSS shaft seal and cause scratches or whatever there. Maybe that was an unfounded fear. Perhaps the PSS seals so tightly that no water ever gets between the two surfaces.

-When there are seal problems that's what is usually the cause...- (i.e., mis-alignment)

This seems to be saying that you have in fact seen seal problems with those units, but you put it down to user error in every case.

Innsurance companies being what they are, if your boat sank due to a shaft seal problem and they discovered that you hadn't replaced the bellows hose in the last three years per the manufacturer's instructions couldn't they weasel out of paying by saying that it was owner error that sank the boat? I doubt if they would accept the argument that you were using heavier hose and therefore it wasn't necessary to change that often. They might even ding you for not using the manufacturer's recommended hose.

I don't have any strong feelings against the PSS system and have no personal experience of anyone having a problem. After looking at the alternatives it's not the way I chose to go is all. I don't say I'm right, I'm just laying out my thinking of the subject to be refuted or considered. I think these kinds of discussions are good because people who installed a PSS system may have forgotten that they are supposed to change the hose every three years and will now go check it. People who went with teflon may wonder if theirs is still drip free or needs adjustment. In fact I haven't checked mine in some time and this reminds me I have to do that next week.

Don't you love a good debate, MacDuff?

Guys,

FYI there are two different types of bellows hose for dripless shaft seals like the Lasdrop, PSS, et al. There is a standard version which is a non reinforced nitrile type rubber that is pretty tough and is specifically used on low rpm engines like small diesels and then there are heavily reinforced laminated bellows hoses for heavy duty high rpm application use. These things are as tough if not tougher than standard shaftlog hoses.

Tom is certainly correct about the seal faces not wearing out. The problems occur when the seal faces are damaged by mishandling when installing or later servicing. My Lasdrop seal has been in the boat for at least ten years now and I have had no problems with it. I did originally install the optional heavily reinforced bellows. I currently prefer the PSS shaft seal but haven't seen the new generation Lasdrop for comparison.

I have seen a few traditional shaftlog hoses that attach stuffing boxes to shaft logs which have had leakage problems over the years and so I believe none of these shaft seal systems are perfect and without risk. Generally speaking from my experiences it is without a doubt more maintenance and more difficult maintenance to have a traditional stuffing box than a dripless seal.

With the heavy duty bellows hose I've never noticed any appreciable loss in flexibility in the hose. The tension pressure can easily be adjusted by simply adding a little more compression to the bellows. The bellows hose would have to be in absolutely deplorable condition to be so deteriorated as to not be able to apply sufficient pressure against the sealing faces to not create a good seal. It doesn't require much tension to mate the seal faces. The key to a good seal with these units is to properly align and mount the bellows hose to the stern tube in the first place, that is a very important step. When there are seal problems that's what is usually the cause of problem. I can say that I have ever seen one of these seals have a bellows hose problem.

Tom, I don't understand the comments about the vulnerability of the surfaces to contaminants such as "barnacle shells". They (barnacle shells) simply can't get to the seal face. The only thing that I have ever seen that has caused a problem with a seal face is physical damage caused during installation such as a deep scratch or heavy nick due to careless handling.

Dripless seals and teflon packing both have advantages and disadvantages. They both rely on a stern tube hose for seal integrity. They both are vulnerable to neglect and lack of maintenance. The dripless seals are easier to deal with from my experiences. More and more manufacturers seem to be using dripless seals every year.

As for the insurance issues posed, my insurance is through West marine and they are well aware the boat has a dripless shaft seal and I have never heard a word of concern about it from them. It is even stipulated clearly in the boats preinsurance survey report she is equipped with a dripless shaft seal.

These are just a few counter views on the dripless seal by a user and a past dealer. We all know full well there are disaster stories surrounding any shaft seal type. It's usually not the seals but the owners or mechanics that are the root of the problem in those disaster situations.

TomCambria@mindspring.com

[Warren Kaplan]

John,
I'm really not the one to answer your questions about the design of the PSS. Frankly, the reason I installed one was because the hose on my old stuffing box was ballooning badly and the maintenance on stuffing boxes was not something I was prepared (physically and mentally) to do. I also was going nuts trying to figure out if I had just the right number of drips per minute from the old stuffing box. I wanted something that was maintenance free, or as close to that as possible. The PSS is hardly a new product. Its been around for a while and I haven't found any glaring indictments of it. Many reputable boat builders are using them as standard equipment now. I talked with some people who use them and they are uniformly happy that they made the change. Why there's no filter on the hose from the exhaust to the PSS, I can't tell you. I left a link to their website on a previous post. They have a "contact" area and maybe they can provide the rationale for the design as it now is.

Warren Kaplan
Sine Qua Non
CD27
Oyster BayHarbor, NY



Setsail728@aol.com

[John R.]

Tom,

Just one last tidbit of info that might help clear up some ambiguities regarding understanding the engineering differences of the Lasdrop and PSS.

The Lasdrop I have (and sold) has the beveled sealing edge on the stainless collar (rotor section) and a smaller beveled sealing edge on the plastic seal (teflon I think but it may be nylon, can't remember for certain, the material was called Duromax). The Lasdrop seals by the contact of those two beveled edges.

The PYI PSS shaft seal on the other hand seals by the contact of two flat faces of comparable size.

See Warren's link to the PSS seal for an illustration of the sealing faces on the PSS seal in the installation section.

Hope this additional info helps.

John

I don't see anyting wrong with your explanaiton or debating skills at all. Your discussion here has made me feel better about that style of seal. I don't recall the PSS seal having a beveled edge. Perhaps that was an later improvement or something unique to Lasdrop. I actually bought a PSS and was about to install it when someone raised many of the issues I raised here to me and scared me out of it. That's mainly why I switched to the teflon style. I still have that PSS unit in the garage somewhere unused and in the original box, and if I can find it, I'll pull it out and have another look at it and the directions.

As far as insurance companies go, perhaps you've had better luck with them than I have. I've never submitted a claim on my boat but I've had a lot of negative experience with car claims. (Where I was the victim not the perpetrator) A hurricane is considered an act of God and thus out of the control of the owner, but I have seem some of them try to weasel out of claims by claiming the problem was owner induced. I'm sure some of them are better than others. I've seen a lot of people try to defraud insurance companies too. But that's a subject for another bulletin board somewhere else.

I any case I've learned a lot from this discussion and I'm sure others have also. One of the great things about this BB is this type of discussion. Thanks for taking the time for such a detailed post. Regards, and as Ken, who started this thread, always says, Keep on Sailing.

Yeah, This is a good discussion. Lot's of good thinking going on.

I think (although my writing skills are in question) that I may be able to help people understand how these seals work. First of all no water goes between the sealing surfaces as is assumed based on some of the comments that have been expressed. Take my Lasdrop for example, it seals on a beveled edge. The plastic teflon section (which clamps into the end of the compression bellows stern tube hose)has a finely beveled edge that rides against a larger beveled edge which is machined onto the other piece of the seal which is the fixed (clamped to the shaft) stainless ring. The beveled edge of that stainless section rides against the narrow beveled edge of the teflon piece, it actually penetrates the teflon section somewhat. That allows the bellows hose and teflon piece to be able to move or vibrate and not cause any leakage. If the two pieces of the seal are off axis to one another it will still seal. The only way leakage will occur is if you manually grab the bellows hose and push it back pulling the seal halves apart. Plenty of pressure is kept against the mating seal halves by the bellows hose,even the standard rubber one which is much stiffer than it looks. The high speed fabric reinforced hose is even stiffer. The best thing to do is look at them in person. They are quite good units and well designed. They aren't some piece of junk some guy threw together in his shed. It's good marine gear but an owner has to follow proper installation methods just like he would with a traditional stuffing box. As we all well know they have vulnerabilities also.

Tom, I don't know if teh average owner would be aware of the difference in hoses between the low rpm unit and the high rpm unit. That is up to the owner and the place where he shops for it. If a person were interested in a piece of gear like these shaft seals they should contact the manufacturer and pose their technical questions rather than depend on an average salesperson in a store. This type of gear is important and a prudent owner will do proper homework before laying down a penny when the security of his boat is at stake.

The reason why I chose to install the heavy duty fabric reinforced hose was because I thought it added more security even though it wasn't considered necessary by the manufacturer on a small diesel. I always recommended the heavy bellows to customers. Some went with it and some didn't. No one that I am aware of to this day has had any problems with either hose. The cost is obviously higher on the heavy duty bellows hose.

When I sold shaft seals there was no recommendation to change hoses every three years. I'm not sure who may be recommending that practice at this time. My unit still has the original hose and there is no reason to change it as it still places plenty of pressure against the sealing faces. I suppose if a hose was weaked or damaged by rusting clamps then changing the hose would be necessary just as it would be with a traditional stern tube hose on a flax stuffing box.

Yes, I would recommend everyone use the heavy duty bellows hose even on a small diesel. I prefer to be on the cautious side when it is possible and at reasonable cost.

The silt you describe would not contact the sealing faces, no water will unless the seal is pushed apart by someone. No water gets between the seal faces once it has broken in after a new installation and the surfaces have mated to each other (about an hours running time). Water that feeds up through the boats stern tube cools the seal but does not lubricate it. It does not function like a traditional flax stuffing box.

Yes, I have seen some seepage from some units or even a spray when the shaft was running. I can recall two cases inparticular. After dismantling the units for customers it was discovered the teflon sections had damage to their sealing faces. These were imperfections on the perfectly smooth flawless face that were caused by rough handling and lack of skill during installation.


If a boat sinks because of a hose not being changed on a dripless shaft seal I truly don't believe it would be any kind of issue with an insurance company. First of all I don't think they would have a clue about the scheduled hose change interval you mentioned. Secondly boats sink for far more stupid and incompetent reasons and they still pay their insured. That's why they are in the risk business and poor slobs like us pay the tab in our premiums to cover the incompetence and caused claims by those who are careless with their boats. I live in the hurricane belt, very few boats are properly prepared by owners but when there is damage they all still get paid. That's the risk business for you! Maybe someone that reads this board that's in the insurance business can give you a professional perspective on claim criteria.

There are several different types of shaft seals on the market, traditional stuffing boxes, dripless shaft seals, lip seals, oil seals, and others. They all have their pros and cons and associated risks. Every person has to decide for themselves what they are comfortable with and can afford to purchase or maintain. Think about seacocks and thru hulls, there are different types and different opinions on them as well. Nothing is cast in stone on this stuff.

<then there are heavily
reinforced laminated bellows hoses for heavy duty high rpm application use.>

I was unaware that there is a heavier gauge bellows hose. That is certainly a plus. Would the avereage guy going in to buy one know that there is a heavier hose available? Wouldn't he look at the information and see that he has a low speed diesel and therefore assume that he should order that hose for his boat? If the nitrile bellows hose is pretty tough, why does the factory itself recommend replacing them every three years? Congruently, does the fact that you put a heavy duty hose on your boat mean that you didn't trust the lightweight hose either, or do you have a high speed engine that requires it? Are you suggesting that everyone should use the heavier duty hose even with low speed diesels?

As far as the barnacle and etc comment goes, I kept my boat in a marina that is very shallow and less than 3 feet deep on a minus tide. It's on a muddy slough and many times you'd be coming in with only 6 inches between the bottom of the keel and the ocean bottom. In very shallow water like that the load of silt in the water eats impellers on raw water pumps, so I just figured without any real evidence that it might get on the surfaces of the PSS shaft seal and cause scratches or whatever there. Maybe that was an unfounded fear. Perhaps the PSS seals so tightly that no water ever gets between the two surfaces.

-When there are seal problems that's what is usually the cause...- (i.e., mis-alignment)

This seems to be saying that you have in fact seen seal problems with those units, but you put it down to user error in every case.

Innsurance companies being what they are, if your boat sank due to a shaft seal problem and they discovered that you hadn't replaced the bellows hose in the last three years per the manufacturer's instructions couldn't they weasel out of paying by saying that it was owner error that sank the boat? I doubt if they would accept the argument that you were using heavier hose and therefore it wasn't necessary to change that often. They might even ding you for not using the manufacturer's recommended hose.

I don't have any strong feelings against the PSS system and have no personal experience of anyone having a problem. After looking at the alternatives it's not the way I chose to go is all. I don't say I'm right, I'm just laying out my thinking of the subject to be refuted or considered. I think these kinds of discussions are good because people who installed a PSS system may have forgotten that they are supposed to change the hose every three years and will now go check it. People who went with teflon may wonder if theirs is still drip free or needs adjustment. In fact I haven't checked mine in some time and this reminds me I have to do that next week.

Don't you love a good debate, MacDuff?

[Ken Coit]

John,

"It's usually not the seals but the owners or mechanics that are the root of the problem in those disaster situations."

Good points! That is certainly true around our boat; I try to keep the others at bay by being an owner/mechanic but that isn't a cure-all either, but I have redone lots of "professional" work in the last three years. Now, at least, I know who messed it up and that I paid fair value for the services promised!

On the other hand, I'd go broke or be fired if I were working in a yard at book rate. They don't pay much dinero for the aesthetic and spiritual satisfactions of working on a boat.

Keep on sailing,

Ken Coit
CD/14 #538
CD/36 #84 Parfait
Hailing Port: Raleigh, NC
Sailing from: Beaufort, NC





parfaitNOSPAM@nc.rr.com