Stern glands - an alternative

[mireland]

I have a Manecraft mechanical seal and have had no problems with it at all. Replace after 5 years at a modest cost and enjoy dry bilges. Is there a reason why so few boat seems to have them?

 

[roly_voya]

Most non-drip seals flood desasterously if the fail, traditional stuffing boxes only drip a bit more. Plus the only spares you need are a lump of greased flax. Dont know how long they last though, current one is 35y...

 

[mireland]

Yes I agree, they would fail horribly. There is however a way of stemming the flow provided with the unit. Once it has been tightened down you can't run the prop any more but at least the boat is watertight again. Still - very scary if you are away from the boat when it fails!!

 

[Ships_Cat]

Many of the lip seal based ones are fine. Apart from the extremely unlikely scenario of a lip seal failing catastrophically I can run ours with the seal out and as long as I keep it pumped with grease periodically it lets very little water in. I have had the seal out a number of times with the boat still in the water and not had a drop come in with the shaft stationery.

John

 

[ianabc]

Nigel Calder wrote about non drip shaft packing in his Boatowners Mechanical and Electrical Guide, page 315, Stuffing Box Blues ...."Drip Free Packing" goo available from Gore (of goretex fame) or from Drip Free Packing Ft. Lauderdale USA ....and it works ...

We packed the conventioanl flax turns with joints staggered and then the green teflon goo.

The shaft is free to turn with a finger push on the prop and no leaks are evident at any engine speed!