PSS shaft seal installation

[Crinan12]

Hi. This is just a request for some re assurance. Does everything here look okay? I'd hate to do something hideously wrong (it has been known).

I still have to attach the breather and fit the remaining set screws.

I am a bit worries that he shaft doesn't sit centrally in the carbon flange (it doesn't exit the flange centrally) but I don't really know what I can do about that?

I have a water feed that was plumbed in to my old deep sea seal but I was just going to do away with it because the PSS doesn't require one.

it seemed an okay job although compressing the bellows and sliding the stainless steel rotor was quite hard due to access.

Thanks

 

[rogerthebodger]

I have had a PSS for 15 years and the only eal issue I have had was that the rotor moved on the shaft while motoring for some time.

I made and fitted a clamp ring to the shaft forward side of the rotor to prevent further movement.

The grub screws are stainless steel and do not bite into the shaft like the hardened grub screws do

Shaft Collars | Double & Single Split Collar | RS

 

[MoodySabre]

It looks okay to me. Provided the compression is right then being a bit off centre shouldn't be a problem. I didn't put a collar on mine to stop it moving and it has been fine for 9 years. You could use a narrow shaft anode but a visual check against the position of that tape. would be guide.
Make sure the vent tube is securely fastened above the water level.

 

[doug748]

It should exit the stern tube centrally but the carbon ring is hanging on the bellows so it's no great indicator of a problem, it tends to be self aligning.

I put a couple of Jubilee clips behind the stainless rotor, you can then use a screwdriver to lever it into compression. I keep the clips in position which allows a visual check to see things have not moved (they never have so far, getting on for 20 years), similar job to your blue tape I guess.

Don't dismantle your water feed. After 10 years my PSS started running dry, I have no explanation for this but it did. The fix was to arrange a positive water feed which cured it, so at least keep this up your sleeve.
I may change back at some stage and see what happens, the vent tube is a simpler and arguably better solution.

.

 

[PCUK]

I had the water feed to mine as it doubled as a vent.

 

[mikegunn]

Personally, I would reconnect your existing water feed to your PSS seal. You will then be assured that there’s little chance of it running dry. It’s not unknown for such seals to be starved of water because of fouling growth around the shaft/cutlass bearing interface. As others here have mentioned, the use of a Jubilee type of clamp around the shaft, backing up the rotor, would be sensible. Should the prop shaft ever slip out of its coupling clamp, it may well prevent the shaft from exiting the boat under reverse thrust!
Mike

 

[iamtjc]

I made and fitted a clamp ring to the shaft forward side of the rotor to prevent further movement

I did the same (though I bought rather than made a split clamp).
Rather than butt it up to the rotor, I left an exact 1mm gap (using feeler gauge).
That way if the rotor slipped the clamp would still be close enough to prevent a big leak but I would be able to reassure myself that the rotor hadn't moved by measuring the gap from time to time.

 

[Crinan12]

Thanks, good to know it seems okay

I was going to but I'll re connect the water feed to it. It needs a bigger bit of pipe than was fitted to my deep sea seal but that's no big deal.