PSS Shaft Seal problems

[30boat]

The Volvo seal is so much simpler and cheaper and apparently lasts much longer than the recommended 5 years. What's not to like?

Exactly,if people will pay more for what is basically an over complicated solution for the same problem then let them.The Volvo seal is cheap,reliable,long lasting and compact.Providing the engine installation doesn't have a lot of movement,which it shouldn't anyway,it provides the best service for the least money and complication.My opinion,not advice.

 

[Squeaky]

I don't feel that your experience is typical and from my memory of it there is some doubt that what you bought was actually made by PSS. I bought mine from Aquafax in UK, where there was no doubt at all as to its manufacture, materials or construction.

Good afternoon:

Any suggestion that the items I was sent were fake came from my post initially because I could not accept that PYI or Seaview could or would provide components that failed so catastrophically. These items were later sent to Seaview in France and confirmed to be original components therefore refuting my belief and suggestion. There is no doubt that the component were original.

You might well be happy with the items you purchased. I had no reason to suspect that the items provided by Deka Marine in Istanbul were anything but original as they turned out to be however the use of PSS seals could have resulted in the sinking of my yacht. Whose fault would this have been?

Mine??? Or Deka Marine??? Seaview or PYI?

I don't know and don't care now but something went wrong which Seaview and PYI are not prepared to resolve and therefore I would not recommend that anyone use this product.

Cheers

Squeaky

 

[Squeaky]

I feel that pss shafts seals are being totaly misrepresented by comments made and no bearing on what is an excellent product, provided that the genuine product is identified,purchased and fitted properly.

Good afternoon Old Troll:

You are welcome to believe what you want however my experience gives lie to your belief that PSS seals are an excellent product. The components that I was send were confirmed to be original genuine products and I resent any suggestion you might wish to make that they were not fitted properly. I believed after the first failure that the fault lie with faulty installation therefore a friend and myself installed the second seal checking each other at each step. I do not accept any suggestion that our installation was in any way faulty.

If you are happy with your PSS seal, continue to enjoy the service it provides but if thinking about buying a new unit, I suggest you think again unless and until you are absolutely sure the same failure I experienced will not happen to your yacht - it could result in your yacht sinking.

Cheers

Squeaky

 

[Old Troll]

PSS shaft seals

Good afternoon Old Troll:

You are welcome to believe what you want however my experience gives lie to your belief that PSS seals are an excellent product. The components that I was send were confirmed to be original genuine products and I resent any suggestion you might wish to make that they were not fitted properly. I believed after the first failure that the fault lie with faulty installation therefore a friend and myself installed the second seal checking each other at each step. I do not accept any suggestion that our installation was in any way faulty.

If you are happy with your PSS seal, continue to enjoy the service it provides but if thinking about buying a new unit, I suggest you think again unless and until you are absolutely sure the same failure I experienced will not happen to your yacht - it could result in your yacht sinking.

Cheers

Squeaky

I was not inferrng that your specific product was sub standard or not fitted properly by your good self. However it is difficult to understand why an expensive pss shaft seal should prove such a disaster and so quickly become a liability. I fitted mine in approx 20 minutes, 5 years ago
and have not looked at it since, but since your warnings shall certainly pay more attention. Anyway I hope you have no farther problems.

 

[doug748]

The Volvo seal is so much simpler and cheaper and apparently lasts much longer than the recommended 5 years. What's not to like?

......500 hours, which, for a lot of folk, is less than 5 years.

Lip seals tend to wear the shaft and then leak.

They are not good if your engine moves a lot.

They are not good if your shaft is suspect in shape, pitted or worn.

The Volvo seal needs to be purged of air and lubricated, or it can overheat. So not so good if you are on a drying mooring or have poor access to the engine room.

Not that I think the Volvo is a poor thing, I would have bought one myself but it was not available in the size I required. It is not hard to figure out a similar list of drawbacks for all stern gear arrangements - all of which are regularly reported as being a pain in the rear end.

I do find stern gear arrangements an odd thing to have messianic enthusiasm for.

However. More to the point there is something not right about this tale of the PSS problem.

1) The photos do not match the vision of any PSS kit that I have seen.

2) Why would the manufacturer supply bits and pieces for a distributer to cobble together? I see no commercial advantage and lots of negatives.

3) If the faulty unit was put together at local level, where did that carbon/graphite flange come from? It is smaller than the smallest unit that the company produce, not being long enough to take the two clips which is a common feature of all the PSS units?

4) Last why is PSS keeping so quiet. Too quiet, we should be told.

 

[Bosun Higgs]

How old are your Volvos and what failure mode/leak did you get to trigger a replacement ?

TIA

The current one is 2 years old and has started leaking. OK its no more than a desert spoonful every 10 hours or so, but I'm firmly of the view that the water should be outside a modern grp boat and not inside it. But my shaft is now17 years old and it has worn a bit in the area the seal sits. The shaft mics at 24.95 reducing to 24.86 in the seal area. Looking at the volvo leaflet on the boat today it gave shaft tolerance at 25mm +/- 0.1mm so maybe thats the reason why its leaking so early.

I think I'm going to replace the shaft and use the Volvo rather than keep the shaft and use the PSS. The mention above of the PSS sticking together if left reminded me of the deep sea seal which I didnt like at all.

 

[chewi]

The Volvo seal is so much simpler and cheaper and apparently lasts much longer than the recommended 5 years. What's not to like?

first off is hanging upsidedown in the bilge to burp it
second off is the need for the shaft to be perfect at the point of the lipseals
third off is they don't make it in my combo of shaft size and stern tube.

all in all v happy with my genuine PSS from Lake.

 

[Squeaky]

However. More to the point there is something not right about this tale of the PSS problem.
1) The photos do not match the vision of any PSS kit that I have seen.
2) Why would the manufacturer supply bits and pieces for a distributer to cobble together? I see no commercial advantage and lots of negatives.
3) If the faulty unit was put together at local level, where did that carbon/graphite flange come from? It is smaller than the smallest unit that the company produce, not being long enough to take the two clips which is a common feature of all the PSS units?
4) Last why is PSS keeping so quiet. Too quiet, we should be told.

Good morning:

All the items shown in the photos above were sent to Seaview in France and they made no comments to suggest that the components were anything but what they should have been.

As mentioned above I spent a lot of time trying to get my head around what might have caused the failure of the two seals I received and have come away with the distinct impression that Seaview and PYI knew what caused the problem but had no intention of telling me. They simply refused to respond to the specific questions I put to them and continually tried to re-direct my attention or simply to create a situation where I would lose interest and go away. They certainly did not react as I thought they would have had they realized how close the use of their seal came to causing my yacht to sink.

As mentioned earlier I would only be too happy to share the correspondence with anyone interested if they let me have their e-mail address.

There has been a number of comments concerning the Volvo seal creating wear on the shaft - I would think that the inside of the seal would wear away long before it created wear on the shaft - rubber against stainless steel. The packing gland seal also was in direct contact with the shaft and survived many many years of use without destroying the shaft.

As said earlier if members are happy with the performance of their PSS seal, good luck to them. I think the basic theory behind the design of the PSS seal makes a lot of sense but my experience with two seals which failed dramatically makes me unwilling to use them again or to recommend the PSS.

I sure would like to know why the manufactures reacted to my questions as they did and makes me wonder what they had to hide. Guess I will never find out but it doesn't stop me from wondering.

Cheers

Squeaky

 

[macd]

Squeaky: sorry to hear of your woes which are certainly alarming.

I installed a PSS seal (sourced from ASAP) and had around eight years trouble-free service from it, which of course in no way negates your experience. Looking at your photos in post #39, I was surprised to see the sleeve arrangement, presumable to make the components to size. Frankly, it looks like a botch in all sorts of ways. It's asking a bit much for a single hose clip to secure the parts...er, securely, in a way that clearly isn't intended in the design. If I recall there should be two hose clips at each end of the bellows. Indeed PSS make this specific claim as to the integrity of the system. The sleeve also makes concentricity an issue. I find it hard to believe that ASAP would have supplied such an arrangement...and yet the people you sourced the seal from clearly did supply it.

Forgive men for not wading through the whole of a long thread, but when you wrote above about evasive replies from the manufacturer, did you mean PSS themselves or their agent?

 

[Squeaky]

Good morning Mac:

There were four clips (two for each end) supplied with the seals I received but, in my opinion, the carbon piece was not long enough and therefore did not fit far enough into the bellow to allow the aft clip to firmly clamp the bellows and spacer to the carbon piece – the aft clip was half on and half off creating the “scissor like” action which cut the bellows. As stated above I am of the opinion that I was supplied with mismatched components but why and how this happened I have not been able to discover from the manufactures.

Something else that has bothered me concerns the bellows – why was the bellows the same diameter at both ends when it was meant to fit a 50 mm stern tube at one end and a carbon piece which had a much smaller diameter. Why did they employ a spacer to fit between the small carbon piece and the inside of the forward end of the bellows – why not simply make the diameter of the carbon piece slightly larger thereby doing away with the need for the spacer. Surely the carbon used is not so expensive that they couldn’t afford to make it a few mm larger especially when one considers the price of these seals compared to the cost of the individual components involved.

I exchanged numerous messages with Seaview in France until they apparently could no longer find a response when I was referred to PYI in America. I did not contact Deka Marine in Istanbul although they were spoken to by the local chandlery from whom I obtained the seals. I didn’t bother them because I believed they simply sent me what Seaview and PYI had provided them.

Cheers

Squeaky

 

[Bosun Higgs]

There has been a number of comments concerning the Volvo seal creating wear on the shaft - I would think that the inside of the seal would wear away long before it created wear on the shaft - rubber against stainless steel. The packing gland seal also was in direct contact with the shaft and survived many many years of use without destroying the shaft.

Surprisingly its always the reverse with lip seals. Whether the type on the Volvo shaft seal or the ones on your engine crankshaft, its the hard steel that wears away whilst the soft rubber seal doesnt to anything like the same extent. At the moment I have a problem also on the rear crankshaft oil seal where the lip seal has worn a groove in the crank. Got round it by displacing a new seal a bit further from the engine and you can of course get the SKF replacement sleeve tube, an option which isnt available on a boat prop shaft.

As mentioned above I spent a lot of time trying to get my head around what might have caused the failure of the two seals I received and have come away with the distinct impression that Seaview and PYI knew what caused the problem but had no intention of telling me. They simply refused to respond to the specific questions I put to them and continually tried to re-direct my attention or simply to create a situation where I would lose interest and go away. They certainly did not react as I thought they would have had they realized how close the use of their seal came to causing my yacht to sink.

I suspect you are correct but what their motivation is I can only guess. Maybe a mixture of American fear of their legal system / claim culture combined with knowledge that some rogue seals had escaped. The Rocna situation again? Head down and hope the problem goes away.

 

[Squeaky]

Good morning again:

I tried to post some images with the latest post above but didn't succeed so will try again - I have made comments on the images which might illustrate exactly what happened:



For some reason I can only upload three images so will upload the last two in another post.

Cheers

Squeaky

 

[rogerthebodger]

I also have a PSS seal fitted to my current boat and an very happy with it. I also have a brand new one I purchased for my previous boat but never fitted.

I comparing my new spair with the pics you posted I note on mine there is no sleeve fitted between the carbon on the rubber bellows as is shown on yours and in in fact the carbon is machined down to a smaller diameter to fit into the bellows. The length of this reduced diameter is about 3 mm longer the the width of the 2 worm drive clips and is 5 mm shorter than the parallel section of the bellows that the worm clips clamp onto.

Also in looking a picture no 4 it looks like there are some marks on the end that fits into the bellows as if the spigot was cut down.

The PSS seal I have in my hand is for a 35 mm shaft and for a 50mm diameter stern tube. The diameter of the spigot is 63 mm and the length is 29 mm.

I also think there was a botch some where and maybe you should do back to your local supplier.

I think you said this was the second failure if so did the first on fail in the same was and was that also from the same local supplier.

OK marks are not cut marks but you were without doubt supplied the wrong size bellows for the carbon seal and some one tried to botch the job.

 

[vyv_cox]

Something else that has bothered me concerns the bellows – why was the bellows the same diameter at both ends when it was meant to fit a 50 mm stern tube at one end and a carbon piece which had a much smaller diameter. Why did they employ a spacer to fit between the small carbon piece and the inside of the forward end of the bellows – why not simply make the diameter of the carbon piece slightly larger thereby doing away with the need for the spacer. Surely the carbon used is not so expensive that they couldn’t afford to make it a few mm larger especially when one considers the price of these seals compared to the cost of the individual components involved.

Which again suggests that both the carbon and the bellows were not the genuine articles. I'm sure you have looked at the pics on my website under <Stern gear<Sternglands, where it is clear that the ends of the bellows on the examples shown have different bores. All the ones I have seen have been similar and the listings of sizes that I have referred to on the Aquafax site all seem to differ in the same way.

 

[Squeaky]

Good morning again:

Think I have succeeded in uploading images:



Cheers

Squeaky

 

[Squeaky]

Which again suggests that both the carbon and the bellows were not the genuine articles. I'm sure you have looked at the pics on my website under <Stern gear<Sternglands, where it is clear that the ends of the bellows on the examples shown have different bores. All the ones I have seen have been similar and the listings of sizes that I have referred to on the Aquafax site all seem to differ in the same way.

Good morning Vyv:

I had not looked at your site previously but have now bookmarked it for perusal later. I couldn't see the bellows you mentioned but the bellows I was supplied had the same internal diameter at both ends for which the spacer was provided to make up the difference at the forward end.

I mailed all the components to Seaview in France at their request which I now regret because I can no longer obtain measurements etc and have to rely on images I took at the time.

Seaview did not indicate that there was anything fishy about the various components they received although I am inclined to think some of the components were not as they should have been but if this is true why did Seaview raise the alarm?

I came as close as I have ever come to losing my yacht and it is driving me nuts that I can't find out what went wrong with what was supposed to be a reliable seal.

Cheers

Squeaky

P.S Great site although I hate to think of the time and effort required to make this site. Congratulations on your efforts.

 

[geepee]

Hi Squeaky

I have also had problems trying to get information from PYI
I fitted a PSS seal last year which had a rubber insert acting as a 'reducer' so the bellows would fit the 42mm log
Unfortunately I was not aware of this and the insert was pushed inside the bellows when fitting it to the log, although it didn't cause any problems with the cuff now being oversize for the log
However, with the insert inside the bellows, I could not achieve the 25mm(I think) bellows compression specified for the shaft.
When I discovered the cuff inside the bellows I emailed PYI many times trying to find out what this extra piece was and why it was inside the bellows - like you I had numerous evasive non replies, until I worked it out for myself !

However, FYI, having removed the carbon block to examine the bellows, I can assure you the carbon block had more than adequate length for the 2 x jubilee clips to be fitted.

Not relevant to your problem but this may be of interest to others; my rotor became quite corroded within 6 months and started to leak, again emails to PYI yielded only evasion, denial of any corrosion issues with rotors and blaming a high level of galvanic action. I don't really buy into this as boat is not in a Marina, there is no shore power and nearby boats are all small yachts with minimal electronics - and no one else suffers from any form of galvanic corrosion.
McDuff were much more helpful and identified the corrosion as 'Pitting', or more likely, 'Crevice Corosion', again PYI ignored these possibilities when I sent photos and asked for their opinion.
I reversed the rotor last year and fitted an earth contact to the shaft but again, within 6 months, there was a significant amount of corrosion, PYI again assured me they had never seen anything like it before.
I have now replaced the PSS with a Radice seal which is like the Volvo seal but has a bleed vent which suits me being on a drying mooring, and less than half the price of PSS.

I am not criticising the PSS seal as it clearly can give many years of good service, however, I am very critical of PYI for their ethos of not responding properly to genuine queries, as you have experienced.

Geof

 

[vyv_cox]

I have carried out a little more research and find I am not quite correct in my last post. This link http://www.shaftseal.com/en/product_categories/300000001?page=2 shows that there is in fact one size in which the hose bore is the same on each end. With a 2 inch diameter stern tube, 1 1/8 inch shaft, the carbon is also 2 inches in diameter. Every other one in the smaller range has different diameters at each end. Your photo seems to show that the carbon was turned down to accommodate the hose, which does not seem to be the standard arrangement.

The minimum length of the carbon cuff is 1.5 inches, same diameter throughout.

 

[rogerthebodger]

The minimum length of the carbon cuff is 1.5 inches, same diameter throughout.

Where do you get that dimension from as the table you pointed to only shows the stern cuff length of 1.5 inch.

On my 35 mm the carbon cuff length as measured is only 29 mm but this is still longer than the width of the 2 worm clips.

I cannot understand that at anytime would there need to be a rubber sleeve between the carbon cuff and the bellows as the carbon cuff diameter can be made to suit the selected bellows.

I can understand that there could be the need to have a sleeve at the stern tube end as this must be supplied as per the boat dimensions so a sleeve for some combinations would help reduce the number of different bellow sizes that would be needed.

As I said before IMHO the sleeve on the carbon cuff is a botch job by some one.

 

[vyv_cox]

Where do you get that dimension from as the table you pointed to only shows the stern cuff length of 1.5 inch.

Not shown in the table but I have many photos of them, never seen one that had a turned smaller radius in them.