Deep sea seal help please

[Sarum28]

Going hard astern (could we have been on the putty?) the spring dounut portion of our deep sea seal wound itself slightly up the prop shaft creating a gap (un-noticed) and a bad leak. Luckily we checked the boat the next day. Jubilee clips not as tight as they should have been so I loosened them and pushed the dounut back towards the rest of the seal and re-tightened clips. Has anybody had similar experiences please. I have heard that there is a plastic gauge for making sure the dounut is back to the right tension. I do not know even which company makes deep sea seals so I can get on to them. Any ideas please.

<hr width=100% size=1>Jonathan & Avril<P ID="edit"><FONT SIZE=-1>Edited by Sarum28 on 04/06/2003 19:47 (server time).</FONT></P>

 

[philip_stevens]

Have a look at this site, http://www.bruceroberts.com.au/chandlery/dss.htm


<hr width=100% size=1>regards,
Philip

 

[Robin]

We have one of these too and the adjustment is very critical. When we bought our boat the engine was serviced and recommissioned by a well known boatyard asked specifically to check/test this seal on relaunch. We later discovered that above 1500rpm the seal opened and water poured in. We had water over the floorboards on our first delivery trip, fortunately realised that it only came in under motor, by then we were sailing and were able to continue. Needless to say said boatyard denied any responsibilty, suggested our surveyor was to blame(he 'examined but did not touch' the seal). or that it was like it before. The boat had just arrived (dry) from Malta with just a couple of days stopover in Lisbon.

Readjustment using the little blue plastic gauge supplied cured the leak but we later replaced the seal since there was a small split starting in the rubber. Since then the seal appears to work well and stays dry, for safety though we added an additional hose clip on the shaft behind the bellows bit as a mechanical stop to prevent any slip in adjustment.

Try www.asap-supplies.com who list Deep Sea Seals, they are based in Beccles, Suffolk, tel 0845 1300 870.

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[Blue_Blazes]

I had my boat sink just before Christmas due to one of these seals which mysteriously came undone one night and the leak overwhelmed the automatic bilge pump. It appears that with age, and anything less than spotless bilges, the rubber softens allowing it to migrate from under the hose clips, which makes it come loose and slide up the shaft. Not very good for something that's supposed to keep the water out.

When I bought the boat a few years ago I was told by the owner that you had to periodically check the condition of the seal and after launching you had to "burp" the thing to ensure it was full of water. What I've since found out is that they are not supposed to be used over a certain rev limit and that their designed life span is only about three years, (mine was a lot older than that). Needless to say, when I finally get the old girl back to seaworthy condition she will not be fitted with one of these sinkers.

Bill.

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[Russell]

We've had a manecraft deep sea seal on the Moody since about 1990, with no problems at all. It even managed 2 almost turn inside out without leaking when we picked up a chain around the prop which pulled the engine back so far it broke the front mounts ! I've always had an extra couple fo jubilee clips round the shaft though, just in front of the seal. I renewed the seal last year when the gearbox went, but the old 1 still looked good after over 10 years service. It has got the water injection pipe connected, because we used 2 b on a drying mooring, which probably helped it last so long.
The plastic tension guage is a bit tricky 2 use, especially when the seal has been used for a while because the part which is gripped around the shaft gets distorted by the clips. This makes it hard 2 b sure that it is being pressed evenly against the fixed face, but about 30 minutes swearing usually gets it.

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[Birdseye]

had one of these which wore and started to drip after only three years. when i complained at the boat show, they gave me a replacement foc. however, i was not convinced and replaced the system with one using lip seals (three) of the sort commonly used in vehicles, engineering etc. spares freely available from your local seals specialist at sensible prices, and it never leaked a drop. cheaper, too.

only issue was that i had to use fully synthetic oil in the reservoir because it got quite warm.



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[Sarum28]

Thanks to everybody who has replied. All most interesting. Anybody know where we can get the plastic gauge for re-setting the donut please?

<hr width=100% size=1>Jonathan & Avril