What to do if your shaft seal leaks?

Good evening:

I find it curious that so many people attempt to poo poo the refusal of PYI or Seaview to admit what happened to cause the failure of these seals which I believe to have been caused by mistakes some place along the line with the assembling of the various components. No one has yet been able to explain where the rubber spacer which fit between the bellows and carbon piece came from as it doesn't appear to be part of any PSS seal.

In so far as as the installer being at fault, I consider this another red herring so to speak as I doubt that everyone who has installed a shaft seal will have been familiar with all types and doubt they would study the design and measurements in detail before following the instructions and installing the seal. It is however a great way of pointing the blame away from PYI and Seaview.

At this point I intend to terminate this discussion however I will be waiting for future posts concerning PSS seals just to make sure everyone is aware of what can happen with these seals.

All of this **** could have been avoided had PYI and/Seaview been upfront and frank about the problem which they decidedly were not - how many people want to deal with such a company?

Enjoy your PSS seals, if you have one, however remember that they can fail catastophically.

Cheers

Squeaky
 
Sorry to intrude on slating of pss seal ,my original question didn't really get answered ,although a lot of helpful suggestions.
The engine had been regularly run in gear and the shaft seal was not leaking in the berth .
.It appears that the cutlass bearing has worn and the shaft is not central in the tube anymore .So now the face of the stainless and carbon parts are not correctly aligned.Hence leak.Pulling the shaft out to sort it .
The owner has commented it has been a problem before.
Maybe another type of seal is now called for at this point and Im very glad I didn't find it halfway across Biscay :)

Vara please feel free to join me with your scrubbing brush any time ,I've have tried Patio Magic but will still need to scrub the Dover dirt off that teak.:D
thanks all. Cindy
 
I would not have thought that was possible. Wear of the cutless bearing cannot account for more than a couple of degrees of shaft misalignment, which the bellows of the PSS can easily accommodate. I shall be interested to hear what is found.
 
vyv_cox said:
If you look at my website http://coxengineering.sharepoint.com/Pages/Sternglands.aspx you will see several photographs of other seals that failed catastrophically. These include several packed glands, Volvo, Tides Marine, lip seal types, etc. In each case they also were the result of abuse of some sort, not due to the design of the seal. Using your logic this means that all these types should be avoided as they might 'sink your boat.'
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If I might just make the point that packed glands do not fail "catastrophically". Some are however unfortunately, attached to the stern-tube by a short piece of rubber tube, which of course can fail. IMHO this method of fitting a packing gland is cheap, shoddy engineering.

Most instances of pipework, with direct connection to the sea, are protected by seacocks. Why make a glaring exception for sternglands or shaft seals?
 
NormanS said:
Some are however unfortunately, attached to the stern-tube by a short piece of rubber tube, which of course can fail. IMHO this method of fitting a packing gland is cheap, shoddy engineering.
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Most of the properly engineered packing glands do have anti torque tabs on both the gland and the stern tube under the rubber connection tube to prevent the gland twisting to such a degree that the rubber tube would fail "catastrophically".
 
vyv_cox said:
I would not have thought that was possible. Wear of the cutlass bearing cannot account for more than a couple of degrees of shaft misalignment, which the bellows of the PSS can easily accommodate. I shall be interested to hear what is found.
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I am inclined to agree with Vyv. My guess is that the shaft has moved in an axial direction and reduced the seal compression when forward and astern was engaged. Might be worth checking the coupling and the motor mounts.

Squeaky- Sorry mate, you are being obsessive. Many qualified engineers have tried to explain to you that what you experienced is likely to have been an installation problem. Equipment suppliers have the right to expect that when you buy a component the installer and customer have sufficient technical knowledge to assess the suitability, and to install the component correctly. Only lawyers believe that manufacturers should have infinite responsibility for anything you might do with their product.
 
Hey Rodger- I have an original copy of "Ag pleez daddy, wont you take us down to Durban, its only 8 hours in the Chevrolet". How long does it take you these days?
 
davidej said:
Can I please stick my oar in here?

Obviously Squeeky had a very unfortunate experience which I followed on his original thread. No adequate explanation for his difficulties has been proven and thus he has one idea and others don't agree.

I fitted a PSS on one of my boats and found it properly engineered and very satisfactory. Why Squeeky's one was neither of these will probably forever remain a mystery but it seem wrong to condemn all PSS seals on the basis of this.

For the avoidance of doubt, I have no interest in any marine engineering company including PSS.
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+ 1 but last time i said anything i also got shot down by Squeeky
 
Driving about 6.5 to 7 as I don't hurry these days. We leave about 6 am, stop off in Harrismith for breakfast then in Escort to coffee and have lunch in the club RNYC at about 1.00 pm.

We spend 3 weeks every 2 months staying on the boat in Durban Marina these days.

By Jeremy Taylor
http://www.youtube.com/watch?v=6RAQP-2sODk

By Leon Schuster

http://www.youtube.com/watch?v=iTSXnVHvNOs

Did you stay in South Africa at any time.
 
vyv_cox said:
I would not have thought that was possible. Wear of the cutless bearing cannot account for more than a couple of degrees of shaft misalignment, which the bellows of the PSS can easily accommodate. I shall be interested to hear what is found.
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I wouldn't have thought so either. In fact, I imagine that if you removed the cutless bearing entirely and pushed the shaft to one side of the P-bracket, then moved the engine such that the forward end of the shaft was pushed hard against the inside of shaft log, in the opposite direction to which the aft end had been pushed in the P-bracket, that the bellows would still have sufficient compliance to allow the carbon to seal against the misaligned rotor.

I'm fact, even if the P-bracket fell off, unless the shaft log is especially short, or the shaft especially thin in comparison with the internal diameter of the shaft log, the shaft simply cannot be misaligned very many degrees before the misalignment is restricted by the shaft log.
 
vyv_cox said:
I would not have thought that was possible. Wear of the cutless bearing cannot account for more than a couple of degrees of shaft misalignment, which the bellows of the PSS can easily accommodate. I shall be interested to hear what is found.
Click to expand...

I wouldn't have thought so either. In fact, I imagine that if you removed the cutless bearing entirely and pushed the shaft to one side of the P-bracket, then moved the engine such that the forward end of the shaft was pushed hard against the inside of shaft log, in the opposite direction to which the aft end had been pushed in the P-bracket, that the bellows would still have sufficient compliance to allow the carbon to seal against the misaligned rotor.

Even if the P-bracket fell off, unless the shaft log is especially short, or the shaft especially thin in comparison with the internal diameter of the shaft log, the shaft simply cannot be misaligned very many degrees before the misalignment is restricted by the shaft log.
 
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Another contributing factor is the engine mounts are not in the best state ,and have allowed the back of the engine to drop.With about 3 mm of rattle on the cutlass and 8mm on the mounts,it's expecting a lot of the shaft seal to put up with that .:(
Cindy
 
Yara said:
Squeaky- Sorry mate, you are being obsessive. Many qualified engineers have tried to explain to you that what you experienced is likely to have been an installation problem. Equipment suppliers have the right to expect that when you buy a component the installer and customer have sufficient technical knowledge to assess the suitability, and to install the component correctly. Only lawyers believe that manufacturers should have infinite responsibility for anything you might do with their product.
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Good afternoon Yara:
Yes, I can understand why you might think that I am obsessive on this subject however I would rather think that I am being stubborn and persisting in trying to force PYI or Seaview to produce an explanation as to why their seals failed twice. In addition to the rights of the supplier I also think that I have the right to receive the correct components for any item I purchase and to expect the manufacture to provide these correct components

I accept that I probably did not receive the normal components for an original PSS seal however would like those who are inclined to put the blame for the failure on the installation to explain why there was a rubber spacer included in the kits I received. Where did this spacer come from? It does not appear to be part of the normal components sold with a PSS seal.
View attachment 32061

If this spacer is normally provided why? Would it be so that the carbon piece could be of a smaller diameter - surely the price of carbon could not be so costly that a manufacturer would have to stoop to this. By the way the spacer is shown facing the wrong direction in the image - the collar should be at the front end of carbon piece.

I would like to be turned loose with a shelf full of these seals to determine what the diameter of the carbon piece intended for use with a 50 mm stern tube should be. It seems logical to me that by using a carbon piece with a smaller diameter that the length of the carbon piece would also be shorter than one would expect from a carbon piece with the correct diameter. Possible one who claims to be familiar with these seals could confirm if 50 x 25 mm seal includes a rubber spacer and if not, the length and diameter of the carbon piece normally supplied with such a kit.
View attachment 32046

If the carbon piece I received was the correct one why was it not sufficiently long to fit fully into the bellows as indicated by the moulded spaces for the clips?

I am left to conclude that I received incorrect components which contributed to the failure of the seals but am none the wiser as to why this happened and in particular if the spacer is not part of the normal items stocked by PSS dealers where the heck it came from?

I am also left to believe that a full sized carbon piece would have been longer and extended deeper into the bellows allowing the aft clip to be fully on the aft end of the carbon piece.

Would appreciate comments from those who claim to be familiar with PSS seals.

Cheers

Squeaky
 
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Oops! .....Read the title, noted over 50 replies and 2000+ views, decided there was a lot of interest from a lot of readers - so clicked on to see whet.

No. Not about age-related incontinence after all...... :o
 
Well Cindy, that got them all going.

Way better than messing about ensigns, anchor choice or which colour buttons on your blazer.

Great sport, what are you going to follow this with? Have to be good.
 
Squeaky said:
[/I]

Good afternoon Yara:
Yes, I can understand why you might think that I am obsessive on this subject however I would rather think that I am being stubborn and persisting in trying to force PYI or Seaview to produce an explanation as to why their seals failed twice. In addition to the rights of the supplier I also think that I have the right to receive the correct components for any item I purchase and to expect the manufacture to provide these correct components

I accept that I probably did not receive the normal components for an original PSS seal however would like those who are inclined to put the blame for the failure on the installation to explain why there was a rubber spacer included in the kits I received. Where did this spacer come from? It does not appear to be part of the normal components sold with a PSS seal.
View attachment 32061

If this spacer is normally provided why? Would it be so that the carbon piece could be of a smaller diameter - surely the price of carbon could not be so costly that a manufacturer would have to stoop to this. By the way the spacer is shown facing the wrong direction in the image - the collar should be at the front end of carbon piece.

I would like to be turned loose with a shelf full of these seals to determine what the diameter of the carbon piece intended for use with a 50 mm stern tube should be. It seems logical to me that by using a carbon piece with a smaller diameter that the length of the carbon piece would also be shorter than one would expect from a carbon piece with the correct diameter. Possible one who claims to be familiar with these seals could confirm if 50 x 25 mm seal includes a rubber spacer and if not, the length and diameter of the carbon piece normally supplied with such a kit.
View attachment 32046

If the carbon piece I received was the correct one why was it not sufficiently long to fit fully into the bellows as indicated by the moulded spaces for the clips?

I am left to conclude that I received incorrect components which contributed to the failure of the seals but am none the wiser as to why this happened and in particular if the spacer is not part of the normal items stocked by PSS dealers where the heck it came from?

I am also left to believe that a full sized carbon piece would have been longer and extended deeper into the bellows allowing the aft clip to be fully on the aft end of the carbon piece.

Would appreciate comments from those who claim to be familiar with PSS seals.

Cheers

Squeaky
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I gave you a perfectly plausible explanation several post ago. Did you not notice it?
 
Simondjuk said:
I gave you a perfectly plausible explanation several post ago. Did you not notice it?
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Good morning:
Yes, I noticed your comments and dismissed them as being an inapplicable "red herring" as there is no comparison between a stand alone seal and brake shoes which must fit and match other items within the wheel - any mismatch would be instantly noticeable.

If you are so interested you might consider and provide answers to the following questions raised above:

1. Is the rubber spacer part of the normal components used by PYI?
2. If not where did it come from?
3. If it is part of the normal components, why is it used instead of providing a larger carbon piece?
4. Was the carbon piece I was provided meant for a smaller diameter stern tuber and therefore shorter preventing it from extending deeper into the bellows thereby allowing the aft clip to fully clamp to the aft end of the carbon piece?
5. Was the action or inaction and waffling by Seaview and PYI what one would expect from a reputable company selling vital safety equipment world wide?
6. Is a purchaser entitled to expect the components he is sold to be the correct components?

Cheers

Squeaky
 
wilkinsonsails said:
Another contributing factor is the engine mounts are not in the best state ,and have allowed the back of the engine to drop.With about 3 mm of rattle on the cutlass and 8mm on the mounts,it's expecting a lot of the shaft seal to put up with that .:(
Cindy
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Cindy- your info that this has happened before got me thinking. Did they replace the special squashing grub screws last time? These are single use and if ordinary grub screws are used there is a good chance that the stainless sealing ring could move and release the sealing pressure.
 
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