Deep Sea Seal Problem?

[Deleted User YDKXO]

There we were yesterday creaming along up the Adriatic without a care in the world when my 'this is what powerboating is about' feeling was rudely interrupted by the engine bay bilge pump warning light blinking on. When I looked down into the engine bay, I nearly had a heart attack. Water was spewing out of the starboard shaft seal like somebody had just drilled a hole in the boat.
My boat has this type of Deep Sea Seal http://www.tnorrismarine.co.uk/manecraft.php. Luckily by tightening the emergency clip, the water flow was stemmed and we made it back to the marina without mishap. I immediately called out an engineer who tightened up all the jubilee clips and pushed the seal body harder against the housing and pronounced that all would be well for the remainder of our holiday. I'm a bit suspicious about that so I've got a couple of questions for anybody who knows about Deep Sea Seals.
First, does it sound like the engineer has done the right thing? Second the emergency clip is still tightened up; should it be loosened off now?

 

[DTIM]

I didnt think they were designed to be run with the emergency clip tight. Last winter we replaced a Deep Sea Seal (the second!) with a traditional stuffing box. We could never get the seal to only allow a 'drip' of water, more a stready flow, no matter how we tightened the clips and or pushed the seal together. We were told it could only be down to alignment isues, but were fairly confident we did not have an issue in this department. The seal never gave us any confidence.

 

[Tranona]

There we were yesterday creaming along up the Adriatic without a care in the world when my 'this is what powerboating is about' feeling was rudely interrupted by the engine bay bilge pump warning light blinking on. When I looked down into the engine bay, I nearly had a heart attack. Water was spewing out of the starboard shaft seal like somebody had just drilled a hole in the boat.
My boat has this type of Deep Sea Seal http://www.tnorrismarine.co.uk/manecraft.php. Luckily by tightening the emergency clip, the water flow was stemmed and we made it back to the marina without mishap. I immediately called out an engineer who tightened up all the jubilee clips and pushed the seal body harder against the housing and pronounced that all would be well for the remainder of our holiday. I'm a bit suspicious about that so I've got a couple of questions for anybody who knows about Deep Sea Seals.
First, does it sound like the engineer has done the right thing? Second the emergency clip is still tightened up; should it be loosened off now?

Suggest you replace those seals at the earliest opportunity. Surprised your high class builder chose such a poor design leaving you to experience just why they are so poor - they are the only design that requires an "emergency" device - essential as they fail in the way that yours did. The best replacement (aruguably) is the Tides Marine seal, which unlike the ones you have uses waterlubricated lip seals so does not rely on the pressure of the bellows to keep face seals from leaking.

 

[Latestarter1]

Seal can leak dramatically if insufficient pressure on seal face, sounds like tec has increased pressure on bearing face seal.

Emergency clip should now be loosened, now look for a drip. If seal is passing any water it has become damaged.

Check that you still have water flow to the seal, interruption of water flow can cause seal failure.

When they came out we referred to them a 'Deep Sea sinkers' however problems have turned out not to be as bad as we had predicted, but concept still makes me feel a little queasy.

 

[jfm]

Suggest you replace those seals at the earliest opportunity. Surprised your high class builder chose such a poor design leaving you to experience just why they are so poor - they are the only design that requires an "emergency" device - essential as they fail in the way that yours did. The best replacement (aruguably) is the Tides Marine seal, which unlike the ones you have uses waterlubricated lip seals so does not rely on the pressure of the bellows to keep face seals from leaking.

Yup, I'd agree all that. The Tides system is best. It also comes with spare seals sitting on the shaft, so that if you need to change the lip seal due to wear you can do it in about 10minutes with simple tools and without disconnecting shaft from gearbox. You just cut the old seal off and slide a new one down into place (though I had >800hrs from the set on my first sq58 and never needed to use the spares).

 

[Deleted User YDKXO]

Suggest you replace those seals at the earliest opportunity. Surprised your high class builder chose such a poor design leaving you to experience just why they are so poor - they are the only design that requires an "emergency" device - essential as they fail in the way that yours did. The best replacement (aruguably) is the Tides Marine seal, which unlike the ones you have uses waterlubricated lip seals so does not rely on the pressure of the bellows to keep face seals from leaking.

Because my boat manual said they were maintenance free, I never took much notice of them but having now understood how they work (or not), I'm not at all impressed by the design and I agree with you. The only force keeping the 2 faces of the seal together is the friction developed by clamping the rubber seal body on the prop shaft and thats almost bound to loosen over time. Having said that, I've spoken to the UK dealer and apparently these Deep Sea Seals are common on large boats so they can't be all that bad

 

[Deleted User YDKXO]

Seal can leak dramatically if insufficient pressure on seal face, sounds like tec has increased pressure on bearing face seal.

Emergency clip should now be loosened, now look for a drip. If seal is passing any water it has become damaged.

Check that you still have water flow to the seal, interruption of water flow can cause seal failure.

When they came out we referred to them a 'Deep Sea sinkers' however problems have turned out not to be as bad as we had predicted, but concept still makes me feel a little queasy.

Have now loosened emergency clip and seems to be dry but UK dealer (Norris) says that by tightening emergency clip I have probably damaged rubber housing, especially since I carried on using that engine to get into marina, and therefore he advises not to use boat. Any views on that? If he's right, it's holiday over unless I can find replacement unit and UK dealer says that could be weeks for delivery. Anybody got any idea where I might get one for 60mm shaft/90mm tube?

 

[Tranona]

Because my boat manual said they were maintenance free, I never took much notice of them but having now understood how they work (or not), I'm not at all impressed by the design and I agree with you. The only force keeping the 2 faces of the seal together is the friction developed by clamping the rubber seal body on the prop shaft and thats almost bound to loosen over time. Having said that, I've spoken to the UK dealer and apparently these Deep Sea Seals are common on large boats so they can't be all that bad

Think that is a bit of marketing speak! The original manufacturer discontinued them several years ago because of all the problems they experienced. They were redesigned - mainly adding that "emergency clamp" feature - but the basic design limitations are still there. They are now made in Australia (not in itself bad - but very few sold in Europe). If you like the idea of face seals the PSS design is much better engineered and seems to give good service - but really lip seals as in Tides Marine (and Vetus) are the way to go. Maintenance free and easy to service if necessary. Most of all do not fail catastrophically - just slowly weep if the seals do wear.

 

[Tranona]

Have now loosened emergency clip and seems to be dry but UK dealer (Norris) says that by tightening emergency clip I have probably damaged rubber housing, especially since I carried on using that engine to get into marina, and therefore he advises not to use boat. Any views on that? If he's right, it's holiday over unless I can find replacement unit and UK dealer says that could be weeks for delivery. Anybody got any idea where I might get one for 60mm shaft/90mm tube?

It is a haul out job to replace them. Norris is also a dealer for Tides, although not sure they do your size. Worth investigating alternatives given your experience.

 

[BartW]

sad news Mike,
I hope you get things sorted to be able to continue your hol's

this is the worse nightmare I have very often, also the last 6 weeks
that you make so much plans, and organise things,
and that the complete plan falls appart due to unexpected technical problems

nevertheless, pls send us a report and pics from your croatia exploration,
where have you been? where else have you planned to go ?
interested to hear/read your report

 

[volvopaul]

Mike, lancing marine should have stock, its in my opinion if you can slide the shaft back and remove the coupling so you can slide the old one off and new one on it can be done in the water if your bilge pumps can pump out what comes in, all of course if there easy to get at, id say its worn out they only leak when the carbon side of it wears a groove in it, which means the ceramic rotating part cannot give a good enough seal.

The emergency clip episode couldhave spun off the stationary part of the seal, what a muppet!, a word of warning if anyone has thoses seals and has to apply the clip then YOU MUST LOCK the shaft from rotating while underway on the other engine.

 

[Deleted User YDKXO]

Thanks for all replies and for Tides recommendation. The Ferretti factory have 2 x Deep Sea Seal sets in stock in Italy which can be delivered to Slovenia tomorrow. I am renting a car to drive to Slovenia tomorrow to pick them up because Croatia is outside the EU and shipping to Croatia is a customs nightmare. Boat is being lifted tomorrow afternoon for engineers to strip out old seals and pull back shafts in readiness for new seals to be fitted Sat morning. All being well, we should be on our way by Sat afternoon but I'm expecting Sod's Law to intervene along the way somewhere.
Had a long chat with Tides and have decided to buy 2 of their seals when I return to UK and fit them over winter when boat is lifted for usual a/fouling. I considered shipping Tides seals from UK but with best will in the world, I probably wouldn't receive them until Mon/Tues next week and in any case its probably least hassle to replace like with like

 

[Deleted User YDKXO]

Yup Bart, this is one of the frustrations of running secondhand boats. They probably go wrong more often than new boats and there's no dealer to shout at when they do. You have to look on the positive side; its an oppurtunity to learn something new about your boat! I know a whole lot more about shaft seals than I did 24hrs ago!
We've been to Vis and had dinner at Roki's with some very nice sailing forumites and then went over to Zori restaurant in the Paklenis. We were planning to go north to the Kornati islands today but it looks like Sat now at the earliest. Still the weather is lovely and I am amusing myself watching Italians park their boats which is an entertainment in itself

 

[Tranona]

Thanks for all replies and for Tides recommendation. The Ferretti factory have 2 x Deep Sea Seal sets in stock in Italy which can be delivered to Slovenia tomorrow. I am renting a car to drive to Slovenia tomorrow to pick them up because Croatia is outside the EU and shipping to Croatia is a customs nightmare. Boat is being lifted tomorrow afternoon for engineers to strip out old seals and pull back shafts in readiness for new seals to be fitted Sat morning. All being well, we should be on our way by Sat afternoon but I'm expecting Sod's Law to intervene along the way somewhere.
Had a long chat with Tides and have decided to buy 2 of their seals when I return to UK and fit them over winter when boat is lifted for usual a/fouling. I considered shipping Tides seals from UK but with best will in the world, I probably wouldn't receive them until Mon/Tues next week and in any case its probably least hassle to replace like with like

Good move. Hope it all goes well. Another piece of (almost!) useless information to file away - you probably won't ever need it again except to make sure your next boat has good seals installed.

 

[BartW]

Boat is being lifted tomorrow afternoon for engineers to strip out old seals and pull back shafts in readiness for new seals to be fitted Sat morning.

so you found a yard / workers that can do the job that quick ? without knowing the people ?
then you are lucky,
must cost a lot ?

are you still on Hvar, or on mainland ? where ?
even from mainland, its a long drive to slovenia.

I'm glad to hear that you could organise all this on so short notice.
good luck with the repair, and enjoy the holiday

 

[aquatom]

I still find it surprising that manufacturers (mainly the usual Italian ones.) still fit such primitive seals when there are the tides marine ones available.

 

[oldgit]

for anyone with an interest..a veritable feast of shaft seals.
http://coxengineering.co.uk/Sternglands.aspx

 

[SAMYL]

I have a Deep Sea Seal on my boat and it has been trouble free for many years although it is due for replacement this winter.
It is important to check that water feed is working correctly as the seal has to be run wet. Those without water feed have to be vented every time the boat is launched or severe wear will result.
I made up a 'spacer' from a piece of split neoprene tube the same size as the shaft. It fits between the flexible coupling and the rubber of the seal so preventing any slippage foreward of the rubber should the clips loosen.

So far it has served me well. Look after it and it will look after you.

 

[Paul1962]

Deep Sea Seals have been and are used on a very large percentage of her Majestys warships. The company have been in business now for a number of years.
Whilst the Tides Marine item is an excellent item, using a lip seal on a shaft will result in the lip wearing a groove in the shaft. This will of course allow more water in no matter how many changes of seal you have. The shaft may also have to renewed as some shaft materials are non-repairable.
Stay with the Deep Sea Seals item - properly installed and looked after, these seals really are one of the best stern seals out there.

Paul

No Relation or vested Interest

 

[MapisM]

Deep Sea Seals have been and are used on a very large percentage of her Majestys warships.

Interesting.
Then again, obviously aquatom knows better than HM warship builders and the "usual Italians"...