Recommend me a stern gland

[purplerobbie]

Is there any give in the radice seals?
I know my shaft is 30.8 mm (1 1/8?) I measured it when I replaced the engine but..
I have no idea what the other end is somewhere about 2 inch I think.
They only come in 48mm. Could you get it on?

If not what are DSS ManeCraft shaft seals like?
They seem to have an easier tolerance.
43mm to 51mm

 

[Tim Good]

If not what are DSS ManeCraft shaft seals like?

Popular apparently but my engineer said they sucked and had a lot of problems with them and there have been reports of the faces sticking together when laid up for a while. That said anything which is popular can't be too bad. If you take an average of all the reports on ybw the volvo seal / radice seems to be the most glowing but Vyv recommends the pss and hes got a lot of experience so that's what I am trying.

 

[Tranona]

Is there any give in the radice seals?
I know my shaft is 30.8 mm (1 1/8?) I measured it when I replaced the engine but..
I have no idea what the other end is somewhere about 2 inch I think.
They only come in 48mm. Could you get it on?

If not what are DSS ManeCraft shaft seals like?
They seem to have an easier tolerance.
43mm to 51mm

Manecraft not a seal of choice. Although the latest ones are improved they "enjoy" a poor reputation and have been out of production in Uk for many years. Having a device for sealing them off when they fail does not inspire confidence. If you are going for a face seal then PSS is the most popular and has more options for stern tube sizes.

As to stern tube fitting on a moulded rubber seal it won't expand to fit larger but may fit an undersized one with packing dependent on the type of tube. So measure it accurately.

 

[purplerobbie]

I'm very tempted by the radice seal but I'm not sure how good my shaft is under the old packing gland.
If it's even a little worn it will leak like mad. Don't really want to replace the shaft too.

The deep sea seal clamps down with jubilee clips so will take imperfections in the shaft better than the others.
It will probably fit the tube better too.

 

[Tranona]

I'm very tempted by the radice seal but I'm not sure how good my shaft is under the old packing gland.
If it's even a little worn it will leak like mad. Don't really want to replace the shaft too.

The deep sea seal clamps down with jubilee clips so will take imperfections in the shaft better than the others.
It will probably fit the tube better too.

The PSS is a better bet and does not require a perfect shaft. Same basic principle as the Deep Sea but much better engineered.

 

[Sandy Bottom]

This is an aside and should just be taken as such, but Manecraft are the leisure version of a seal produced by Deep Sea seals, who are in turn evolved from Crane Packing, and ultimately Wartsila - perhaps the finest marine diesel engineers on earth at present. The original deep sea seals are the best ever produced and were used for nuclear subs including ballistic boats and had the best performance of any seal on earth - the limit was reached at a shaft seal diameter of +/- 1 meter at full test deep diving depth and the 'emergency - backup' was designed to be used after the main seal springs (they don't just use the compression of rubber at those depths /diameters) had shattered following a depth charge attack - that inspires confidence in me if not Tranona! Don't take the post too seriously in the context of a leisure shaft seal - I use a PSS and it has now been fitted for a couple of decades.

But for ultimate use there is no shaft seal company on earth that can compete with Crane / DSS. Use includes Cruise ships and Ice-Breakers.
http://www.wartsila.com/products/marine-oil-gas/seals-bearings/sealing-solutions/wärtsilä-stern-tube-seals-water-lubricated

 

[macd]

Here's the link to the range of sizes for the Radice (RTMF) seal on the Silette site:
http://www.sillette.co.uk/price_pdf_files/deep_sea_mane_craft_shaft_seal.pdf

Cheaper than the Volvo seal and easier to live with.

 

[temptress]

I need to replace my stern gland and I don't know what to go for?
PSS?
Stuffing box?
Blackjack type?

What do people recommend?

I have been researching this fort he last couple of months and just last Friday asked the yard to fit a PSS shaft seal. Seems to me to be the most reliable option these days. My second best option was to go back to a good old fashioned stuffing box.

So PSS get's my vote.

 

[vyv_cox]

I have a PSS and have had some issues balancing the Stainless ring to prevent wobble. It seems people love or hate them and I'm in the middle at the moment. I like how there is no contact with the shaft at all.

Difficult to understand how the stainless rotating collar can wobble unless it has not been made correctly. The collar is long enough that it cannot lie unfairly on the shaft, provided it is the right size. On my one inch shaft I have to apply a little detergent to enable sliding it along, as it is a good tight fit with the O-rings in place. I assume you have checked dimensions? The only other possible seems to be that with grub screws at 90 degrees in the coller, one is far tighter than the other and has compressed the O-rings on one side.

 

[apollo]

Stuffing box, basic, little to go wrong, if correctly adjusted no grease or water in the boat, last for ever

+1
Have yet to see a new design that is actually better

 

[doug748]

I have been researching this fort he last couple of months and just last Friday asked the yard to fit a PSS shaft seal. Seems to me to be the most reliable option these days. My second best option was to go back to a good old fashioned stuffing box.
So PSS get's my vote.

Same here really. I have had a PSS for many years and like it.

One disadvantage of the patent solutions is that shy manufacturers put very conservative lives on component bits. Thus, should you come to sell, a surveyor will stroke his chin and say the rubber bits need replacement and the buyer wants 1000 quid to fix it. Same deal with saildrive rubber bits. We all know that these parts last a dam long time and the new owner will probably pocket the discount. Just a little point to consider if you might be selling in the medium term.

 

[Piddy]

If you can fit it a Volvo or a Radice moulded one piece gland is the simplest cheapest smallest and easiest to maintain type.

+1

 

[Tim Good]

Difficult to understand how the stainless rotating collar can wobble unless it has not been made correctly. The collar is long enough that it cannot lie unfairly on the shaft, provided it is the right size. On my one inch shaft I have to apply a little detergent to enable sliding it along, as it is a good tight fit with the O-rings in place. I assume you have checked dimensions? The only other possible seems to be that with grub screws at 90 degrees in the coller, one is far tighter than the other and has compressed the O-rings on one side.

Vyv, indeed I think your comments are correct but you may find this interesting for future feedback to others....

Ok so my gland wobbled like hell leaving carbon deposits and water dripping in. See video below and slow mo bit at the end. It looks worse in real life. Anyhow, it was clear that any wobble must be coming from the stainless. So I removed all grub screws and slid it right up and allowed the bellows to push it back evenly. I then engaged drive and it was smooth without wobble. I then began to evenly tighten the grub screws. I mean very very gentle and as evenly as it is physically possible do it. Took 15 minutes over it. Once all tightened the wobble is back.

I did it again, slid it back, let it settle and then slowly tightened the 3 grub screws. wobble was back.

I then tried to undo grub screws to see if one was unbalancing it. I discovered that it would balance with 2 of the 3 screens in place but not a 3rd. I then saw how the PYI PSS seal actually only has 2 screws in their demo video whereas my Michigan PSS has 3. Coincidence? Probably not but either way I now have it reasonably well installed without wobble and with only 2 screws + a jubilee clip for safety.

We go for a week cruise on Saturday and I will monitor.

NOTE: The Michigan seals are in fact made by Maucour - http://www.maucour.fr/photo/fiche-60.pdf

 

[Boo2]

Stuffing box, basic, little to go wrong, if correctly adjusted no grease or water in the boat, last for ever

+1. Just replaced my engine, fuel tank, p-bracket and prop shaft. Only parts of the old system I retained were the stuffing box and prop, nothing wrong with either and I'd much rather have the possibility of an occassional drip to the chance of catastrophic failure if a modern seal goes. In fact the current setup seems faultless and completely dry.

Boo2

 

[doug748]

I binned my conventional stuffing box because the rubber boot was cracking - there's your catastrophic failure waiting to bite yer bum.

 

[tidclacy]

I have a PSS seal and did have problems with it until I got the correct compression on the Bellows and now have no problems. You cannot really do it by hand, managed to get a clamp on it to get the right pressure. The instruction video I note does not show how to do this.

 

[Tim Good]

I have a PSS seal and did have problems with it until I got the correct compression on the Bellows and now have no problems. You cannot really do it by hand, managed to get a clamp on it to get the right pressure. The instruction video I note does not show how to do this.

What problems did you have without the correct compression?

 

[GHA]

I binned my conventional stuffing box because the rubber boot was cracking - there's your catastrophic failure waiting to bite yer bum.

How old was the rubber boot ?

 

[scottie]

Which anchor corresponds to which stern gland?

 

[GrahamM376]

What's your bilge like? If it's deep and damp anyway, the occasional drip from a stuffing box won't matter and you'll have something simple, reliable and easy to service which won't need replaced after five years. If you have a shallow bilge with dead spiders and occasional specks of dust only in it, go for something exotic but be prepared for greater expense and a relatively short service life.

And paying for lifts when it goes wrong. Good old fashioned stuffing box can be sorted in the water.