PSS stern seal

[rogerthebodger]

Inspecting my PSS stern seal today I noticed a build up of crud on both the carbon stator and the stainless rotor.

There was no water leak until I ran the engine and prop then water started to spray out from the face seal.

Could the crud also have built up between the faces if so what is the best way to clean the faces.

I am coming out tomorrow for an wash and antifoul so could fix the issue at the same time.

 

[MoodySabre]

There's a YouTube on this. Suggests initially to use a rag between the two faces. If not enough then use 600grit sandpaper folded in half and work it round a few times. When in the water there should be a small Initial leak to flush the gunge out.

 

[Tranona]

Inspecting my PSS stern seal today I noticed a build up of crud on both the carbon stator and the stainless rotor.

There was no water leak until I ran the engine and prop then water started to spray out from the face seal.

Could the crud also have built up between the faces if so what is the best way to clean the faces.

I am coming out tomorrow for an wash and antifoul so could fix the issue at the same time.

That is one of the major downsides to the design. Face seals are fine in fresh water and run regularly but can suffer from crud buildup in seawater and left for long periods without turning. Worst case is the faces get so stuck together and when the shaft does turn under engine it causes damage to the faces or rips the bellows.

So, in my view not he best for typical yacht use - particularly in warm seawater and on boats that are used infrequently.

However if inspected regularly and kept clean perform well - just not maintenance free.

Personally I think lip seal designs are superior in leisure boat applications.

 

[vyv_cox]

I flush my PSS in fresh water at lift out to overcome crevice corrosion problems on the rotor. I have not had any salty deposits in 6-monthly stints.

 

[doug748]

I flush my PSS in fresh water at lift out to overcome crevice corrosion problems on the rotor. I have not had any salty deposits in 6-monthly stints.

I have never seen much of this either. MoodySabre has the fix.

The stuff about the faces sticking has all the hallmarks of a urban myth. I think it started on an American board when some people got aerated and started making things up. Of course these things take on a life of their own and get repeated by people who are stuck for an informed comment.

Some years ago, when I hauled out, I tried very hard to get some sort of sticking action but failed, even after drying out the seal with a hot air gun.

There are drawbacks to the PSS but I like the elegance.

 

[superheat6k]

When I changed the 15 year old PSS seals on my Turbo 36 they were well past 'pretty' but not a droplet leaked into the boat (I change the because the cutless bearings were shot). Best shaft seal for small boats IMHO.

 

[rogerthebodger]

Thyks Guys

I have had my PSS stick but I do tend to leave my boat for up to a month or more at a time without any movement.

I also keep my boat all year round and only slip boat once every 2 years for antifoul.

Will try the rag or 600 grit paper.