Volvo Shaft Seal and Tides Marine Shaft seal

[FullCircle]

For those of us who dry out regularly ( an uncommon thing in Scotland I know) I have struggled for 3 years to keep my bilges dry.

Jeanneau in their infinite wisdom installed the Volvo Shaft seal as standard on all thier boats with shafts. Peculiarly, they also install them dry, which leads to early failure of the first one.
You may all be aware that you need to burp the Volvo shaft seal , especially after you have dried out. To do this on Full Circle involves a major mattress moving exercise and no small amount of inconveniance. It also does not guarantee success all the time.

So, after due consideration, I have bought a Tides Marine shaft seal, which has a different seal arrangement, but, more importantly, is self burping, because it has a water feed from the engine cooling circuit which supplies the sealing lubricant(water) in large quantity, which then drains out of the stern tube fitting.

This 110 quid investment is the last straw in my battle for a dry Jeanneau. If this does not work, I am going to sell it and get something else.

I will report back with progress as we go on.....

[Silkie]

This 110 quid investment is the last straw in my battle for a dry Jeanneau. If this does not work, I am going to sell it and get something else.

Jeez Jim! I knew you were having water problems but...

[Rowana]

You may all be aware that you need to burp the Volvo shaft seal , especially after you have dried out.

Not having either a Volvo engine, or indeed a Volvo shaft seal, I'm curious about the "burping". It's not something I've come across before.

Could you explain, preferably in words of one sylable for a numpty like me, what this is all about. Either that, or point me in the direction of somewhere on this interwebby thing where I can read about it.

Rowana has a grease thingy which I just screw down a couple of turns each time I start the engine. Seems to keep the bilges reasonably dry.

Cheers
Jim

[FullCircle]

You have to give the thing a squeeze to expel the air from it. The water actually forms part of the seal.
My old grease thingy on the Evolution 25 worked well, never had a leak with that.

[Rowana]

What do you have to squeeze?

Is it something where the shaft goes into the stern tube?

Sorry if I sound daft, but I just can't picture what you are speaking about.

[ash]

What do you have to squeeze?

Is it something where the shaft goes into the stern tube?

Sorry if I sound daft, but I just can't picture what you are speaking about.

This me 'burping' my Volvo haft seal. Rather than trying to squeeze it, I have inserted the plastic sleeve which is used to protect the seal when sliding it over the shaft, and twisted it so that the air can escape. I was surprised at how long, and how quiet the process was - I had expected to hear a hiss. I would recommend wetting the end of the seal with a detergent/water mixture so that you can monitor the escape of air by seeing the bubbles. The pic shows a trickle of water after all the air has escaped.



Ash

[aquaplane]

Seminole is a Jeaneau (1982) and that has a stuffing box stern gland.

As I understand it a stuffing box is designed to drip as the shaft is turning as the water helps with lubrication.

I thought the only way to have a dry bilge is to have a mechanical seal, from working with them, mechanical seals, I'd stick to a stuffing box. They may drip but they are low tech and even I could fix one.

[Rowana]

Thanks for the pic Ash.

It seems a bit of faffing about to me.

Would it not be possible to fit some sort of small siphon tube so that the air is expelled as the water rises? Or is there some cunning reason not to do this that my, admittedly simple, brain can't see?

[oldgaffer1]

Would it not be possible to fit some sort of small siphon tube so that the air is expelled as the water rises?

I have this arrangement with the PSS shaft-seal (http://www.shaftseal.com/) that I fitted three years ago. The vent tube swan necks up into the aft cockpit coaming. It save a lot of faffing about 'burping' the seal as the inboard end of the stern tube is very difficult to get at on 'Sagittaire'.

Cheers,

Alister.

[So_Sage_of_Lorne]

Funnily enough, I was talking to the production manager of a quality British Yacht builder only yesterday about this very subject.

They stick to stuffing boxes because, in the event of a failure, the stuffing box will drip a little whilst the other device will let go in a big way!

If you can find a dry type seal which doesn't fail to danger please let me know.

[damo]

Seminole is a Jeaneau (1982) and that has a stuffing box stern gland.

As I understand it a stuffing box is designed to drip as the shaft is turning as the water helps with lubrication.

I thought the only way to have a dry bilge is to have a mechanical seal, from working with them, mechanical seals, I'd stick to a stuffing box. They may drip but they are low tech and even I could fix one.

That's all very well if you have easy access for the maintenance. My stuffing box could be just touched with one hand, so without lifting the engine I couldn't renew the packing. So one engine lift and one new hatch in the aft cabin later, I am fitting a Volvo seal.