Water lubricated stern gland.

tt65

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Reviewing the jobs I need to do when craned out next week I realise that I know nothing about the water lubricated stern gland that was fitted in 1999, do not even know the make but possibly VETUS.
So a few questions.

How can I tell that water is passing through the thing? It has a pipe from the engine inlet feed, immediately adjacent to the engine inlet seacock.

Does it need any maintenance?

What checking should I do?

Is it likely to die in its 11th year?

If it helps at all W.Fulmar, Bukh DV 24, Bruntons 3 blade Autoprop.
 
Reviewing the jobs I need to do when craned out next week I realise that I know nothing about the water lubricated stern gland that was fitted in 1999, do not even know the make but possibly VETUS.
So a few questions.

How can I tell that water is passing through the thing? It has a pipe from the engine inlet feed, immediately adjacent to the engine inlet seacock.

Does it need any maintenance?

What checking should I do?

Is it likely to die in its 11th year?

If it helps at all W.Fulmar, Bukh DV 24, Bruntons 3 blade Autoprop.


A very novel way to feed the gland since there is no pump involved. Unless your cutlass bearing has some sort of pump inside it I can't see how this would work at all.

Mine is fed from the positive pressure side of the engine seawater pump via a T bleed off the anti syphon loop between the seawater pump and the heat exchanger.

With the boat out of the water it's easy. Engine running and being fed water from a bucket, water runs out of cutlass bearing regardless of whether in gear or not.

At least one person I know has cut off the water feed to his lubricated stern gland without any adverse affects in years and years. My understanding is that they are more for flushing out sand and grit from muddy berths rather than any 'lubrication' purpose, after all the whole assembly is under about 5 psi water pressure from the sea outside.

AFAIK the Volvo dripless stern glands are supposed to be replaced at regular intervals but for the life of me I cant remember what it is. I have a spare on board but haven't replaced mine since I fitted it about 4 years ago. I think I have to split the shaft from the gearbox to slide a new one in and I'm damned if I'm doing that unless the seal is actually leaking!

When launching they should be 'burped' ie: pinched to allow a dollop of water in around the seal and to let any air out but I cant see why if the thing is fed with water from a pump anyway!. Still I do mine when I launch just to make me feel like there is something I need to do!
 
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How can I tell that water is passing through the thing? It has a pipe from the engine inlet feed, immediately adjacent to the engine inlet seacock.

It might be there just to try and ensure that an airlock cannot exist in the stern tube, though it seems odd. The newer PSS seals use an open tube, vented well above the waterline, to the same end.
 
A very novel way to feed the gland since there is no pump involved. Unless your cutlass bearing has some sort of pump inside it I can't see how this would work at all.

The engine seawater cooling pump will pull water through the stern tube and seawater inlet at the same time. Any air trapped will be pulled through at the same time.

I believe that on a Fulmar, the Cutlass bearing is located further aft from the stern tube in the P bracket, so it would have no effect.
 
Our Beneteau has one

Our Beneteau has one .. It has its own feed from an inlet under the transom .. When we get to the boat I undo the seacock and press the sides of the rubber in so that it goes oval and this lets the air out and the water in .. Ours requires waterproof grease a couple of times a year .. Not a vast amount .. There is a plastic piece which fits over the prop shaft .. It has a gap and you put the grease in there .. :D
 
Our Beneteau has one ...Ours requires waterproof grease a couple of times a year .. Not a vast amount .. There is a plastic piece which fits over the prop shaft .. It has a gap and you put the grease in there .. :D

No doubt true for yours, but this is not generic advice. According to their literature, neither oil nor grease should be allowed anywhere near a PSS seal.
 
I have the Eliche Radice version which is similar to the volvo one but with a water feed pipe so it doesn't need burping. With this it recommends pressure water feed for high speed motor boats but for sail boats just a vent hose above the waterline is sufficient to allow air to escape. This is why I chose this over the volvo version as boat sits on a drying mooring. The only way of checking to see if water is feeding through is to remove the hose & start the engine. If theirs a flow of water then you'll know it's feeding into the seal ok..
 
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