Manecraft Deep Sea Seal Leak

[DrGonzoMIA]

Hi all !

So....onto the next problem. Owning a boat is relentless isn't it ?!
Got engine running, upgraded exhaust system, got the steering working, sorted some dodgy electrics and plumbing.... and now - the stern / shaft seal is leaking
Does anyone have any experience of these Manecraft deep sea seals ? Is there anything I can do before a replacement ? And is it a boat out of the water job ? Any info will be helpful.

You can see on pics where its leaking on the base. Seems to only be happening when the engine and cooling system are running at the mo. Noticed it filling the bilge when I had it running yesterday. Didn't have the shaft spinning. May just be water from the coolant going into it ?

Many Thanks

 

[scottie]

Their recomendation is a 5 year life span and as they are dated 94 it would appear well overdue

 

[Bandit]

I had Deep Sea Seals on my boat, they rely on the spring back of the rubber seal when you push it back to rotate against the "spring back" of the rubber. Mine were six years old. They were perished and cracked when removed there was no Spring Back ie they were perished.

They should not leak at all, they should be replaced completely after 5 to 7 years.

I binned mine and fitted Tides Marine Seals, they are far superior but a 7 year life. Don't do PSP seals.

 

[DrGonzoMIA]

Main question I suppose Is can the job be done in the water? Forgive my lack of knowledge as it may be a daft question ?

 

[Bandit]

Main question I suppose Is can the job be done in the water? Forgive my lack of knowledge as it may be a daft question ?

It cant be done in the water, hoist out, block off, remove shafts and fit new. Go for Tides marine with twin supply if a twin engine boat.

 

[Tranona]

You may well struggle finding a replacement to fit that space. They are not good bits of kit, although having a fixed thrust block means that their biggest weakness - lack of tolerance to movement of the shaft is less of an issue. As suggested Tides Marine is perhaps the best alternative being much more robust and relying on lip seals around the shaft rather than face seals under pressure. Not a trivial job to remove the props and shafts to replace them. You can stop the leaks for now by screwing in the clamp, but you can't then use the engines.

 

[DrGonzoMIA]

Well that's me truly gutted....getting it out of the water is going to be an issue as its on the canals at mo and places nearby only do narrowboats. I booked it into a dry dock in May 2023 as the waiting list is that long. But can't really wait until then as I was to take it out and about.
I have found a few websites which do the Manecraft type seals. It is a very tight space for the seals. But toward the engine is a big universal joint. So I suppose my tactic would to unbolt that from the gearbox and slide the prop section out. Hopefully giving me enough room to slide the seal off the stern tube side?
What a pain in the a**e

 

[Bandit]

Definitely not an in water repair. Unless you want to risk shaft size holes letting in water.

If you have rope cutters they need removing first and refitting last.

You need to either partly or fully draw shafts, to fully draw shafts the props need to come off.

Probably a good idea to replace P bracket and stern tube cutless bearing at the same time and if twin engine do both sides. You also need to think carefully about water feeds and flow rates for cooling water from the engine to the stern tubes. For Tides Marine you need about 4.5 litres per minute for a 2 inch shaft at tick over and a secondary supply for each stern tube from the opposite engine.

 

[Tranona]

You have a very unusual stern gear arrangement. Would be helpful to see more photos internally showing the gearbox and externally how the shaft comes out of the hull and the location of the propeller in relation to the rudder.

 

[Nauti Fox]

I've got them on mine, and one of them was dripping from shortly after we'd bought it, a giveaway was the seal on the clamp was broken.
I decided to go with the same as it was the easiest option, I have read that they are not well regarded but I did it anyway.
There was enough room to remove the old and fit the new with the shafts pushed back, propellors still attached...but the coupling needed a better puller than I had so it was put in the hands of Kevin from Kent Marine Services who got the flange off using a fifteen ton puller, he did an exemplary job, turning up on time and charging what he quoted.
Been drip free ever since.

 

[BartW]

It cant be done in the water, hoist out, block off, remove shafts and fit new. Go for Tides marine with twin supply if a twin engine boat.

onather vote for Tides marine,
defo out of water job !

 

[DrGonzoMIA]

Few pics here. Hopefully found a place to carry out work in June so everything crossed that I can get it done in good time so I can use the boat this summer.
Appreciate the recommendations on gear to use. But if its easier to swap like for like then I'll go in that direction I think.