Shaft seal water feed

[MoodySabre]

I had my reservations but they were unfounded. 4lt/min is only a small amount compared to the output of a raw water pump.

[maej]

Couple of suugestions. To fit a Volvo seal you can sleeve your existing tube out to 1 3/4" to take a standard 1" shaft size seal.

That sounds like a good work around.

I've just gone back and read the brochure http://www.volvopenta.com/SiteCollec...0%28Eng%29.pdf and it says not suitable for use with a flexible coupling... is that a definate restriction or a guide? My current setup is flexi coupling, stuffing box on a bit of rubber tube, P bracket.

[Tranona]

Not sure why they say that as the whole idea of a flexible coupling is to reduce movement of the shaft relative to the engine. From what I have seen plenty of OE installations such as Beneteaus and Jeanneaus (and earlier boats such as Westerlys) use them with flexible couplings. Mine was originally used with a bouncy Yanmar 1GM and a Bullflex coupling (now a Nanni 14), but the shaft does not float as it has bearings at both ends of the tube.

One of the less obvious features is the fluted rubber bearing that takes up most the length and effectively acts like a cutless providing some support for the shaft.

[exfinnsailor]

Get a collar made for your housing that takes it from 1 1/2" up to 1 3/4" wall thickness of 1/8" will be Ok. Glue it into place and fit your Volvo seal. They make a 1" to 1 3/4" . It will be cheaper than messing about with other versions and will probably last longer. Any decent engineering shop would make one for you it's hardly rocket science

Sorry Tranona missed your post .. Great minds think alike

..

[Simondjuk]

The PSS is a possibility and I know of another Sadler 34 that uses one, but I can't help but be swayed by all the hype over them. Still, my current thinking is I would rather the face seal than start messing around with my engine coolant.

So we have Radice and PSS that can both be vented without forced cooling.

Can anyone tell me the distance between stern tube and the bit of a PSS that sits on the shaft? Potentially if it is longer than my old seal I won't need to replace the shaft as it will sit on an unworn bit which would be a nice saving

Where in the UK can the Radice seals be bought from?

What's the hype you hear? All I hear is that they generally give many years of trouble free service.

The total lengths (both uncompressed when fitting and compressed once 'set') are given here... http://www.shaftseal.com/en/categories/300000001

I fitted one recently and found it to be a well made piece of kit, a breeze to fit and it sealed straight out of the box, with barely a mist or any dust when first run.

The one concession I have made is to back up the grub screws in the rotor with the addition of a couple of jubilee clips on the shaft immediately forward of it to prevent the rotor moving up the shaft should the grub screws lose their grip on the shaft. They probably never will but why not have a safeguard when it's so easy to provide.

[David2452]

Worth a mention that the VP seal can and often is used with an open vent or a pressure feed and then needs no burping or lube, the lube is only to help untill the water gets there properly on non vented aplications.

[keesvugts]

For what it is worth, I have a pss seal on a Sadler 34 for 2 years, simply vented without any leaks or problems. There are two O ring to seal against the shaft so a little wear is no issue. Seal runs cool even with 20 hours non stop motering. Result nice dry and clean bilge, much better than the old stuffing box.
Staight forward to fit, O rings are a tight fit and the grub screws are backed up, nut. The suggested hose clamp as additional safety is a good idea.

[maej]

My current stern tube has 2 dogs protruding outward that are supposed to engage with the stuffing box. Should these be cut off for fitting one of these other types of shaft seal? Sorry for the dum question.

[Simondjuk]

Yes, with the PSS you do need the forward end of the tube to be circular to accept the seal bellows, but only for the insertion depth of tube into bellows which isn't that huge.

[Ridax]

Worth a mention that the VP seal can and often is used with an open vent or a pressure feed and then needs no burping or lube, the lube is only to help untill the water gets there properly on non vented aplications.

I don't think the VP seal is available with a connection for pressure feed or venting. It is probably the Radice seal you are thinking about in that case.

I have the Radice seal with venting. Only used it for one year, so has nothing special to report, but so far it is working well at least. Another improvement with the Radice seal over the VP seal is that it is easier to apply grease.