How often to replace a shaft seal?

[SVTatia]

Originally Posted by skalashn

Shaft vibration will cause the Volvo seal to wear prematurely and leak. Mine did. Replaced with PSS, not a drop of water in 5 years, maintenance free.

I had a PSS on my last boat but only because it was steel boat, I didn't know there were other alternatives to the bronze ones. But I was constantly checking it due its vulnerabilties, and I had leaks due to debris being caught in the connecting surfaces and I was always cheking the bellows pressure. A bit of paranoia I guess, but I never really trusted it.
The Volvo one seems to be more robust because it is one piece and there are no moving parts, is this the case?

[skalashn]

Originally Posted by SVTatia

I had a PSS on my last boat but only because it was steel boat, I didn't know there were other alternatives to the bronze ones. But I was constantly checking it due its vulnerabilties, and I had leaks due to debris being caught in the connecting surfaces and I was always cheking the bellows pressure. A bit of paranoia I guess, but I never really trusted it.
The Volvo one seems to be more robust because it is one piece and there are no moving parts, is this the case?

There is no bronze in the PSS seal. The rotor is stainless steel. Carbon stator surface is mated to the rotor and there is no way anything will get between the surfaces, if correctly installed. I also added a backup collar on the shaft to prevent the rotor from ever sliding up. Did not touch the system in 5 years.

I believe you might be describing a different product.

The Volvo seal has steel shaft moving against rubber...I am actually surprised they last as long as they do.

[Dockhead]

That seems like a pretty short life.


I have a Tides Marine Sure Seal dripless seal in my boat. The original one was 16 years old, and 3000+ hours, when I replaced the lips just in case. It was still perfectly drip free and probably would have gone for years more. No maintenance of any kind, no lubrication with anything.

[SVTatia]

Originally Posted by skalashn

There is no bronze in the PSS seal. The rotor is stainless steel. Carbon stator surface is mated to the rotor and there is no way anything will get between the surfaces, if correctly installed. I also added a backup collar on the shaft to prevent the rotor from ever sliding up. Did not touch the system in 5 years.

I believe you might be describing a different product.

The Volvo seal has steel shaft moving against rubber...I am actually surprised they last as long as they do.

You did not read it correctly - what I meant is that I installed the PSS to avoid installing the "common" bronze shaft seal in my steel boat. It was installed properly and and yes, on occasion, small debris would get in between the mating surfaces.

[Martkimwat]

Volvo recommend replacement every five years or 500 hours whichever comes first. Seems to be similar for most silicon rubber lipped shaft seals. I believe the graphite/stainless steel faced seals last longer, but of course cost at least four times as much. It's a case of 'yer pays yer money and takes yer choice', or 'you get what you pay for.'

[hd002e]

Pulled off the shaft seal and it looks shredded on the inside. I got a new one and I will be replacing it.

Does this point to another problem elsewhere? (Like a misaligned motor mount?) or does it look like I was a bit rough while installing the shaft three years ago?

The cutlass on the p-strut seems tight.