Changing the bellows on PSS Shaft seal

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FairweatherDave

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I changed mine 4 or 5 years ago. No real difficulty. Essentially just removing the old assembly, replacing the bellows and refitting as for a new seal. Check the shaft for any surface imperfections that might damage the rotor o-rings as you slide them on.
I ordered my bellows from Sillette-sonic, but it came from Aquafax IIRC.
My main issue was that I found the new bellows much more difficult to compress than the older one. In fact, I never managed to achieve the recommended compression figure, and my enquiries gleaned no useful information, except a rather uncertain "the design seems different now".
Anyhow, it's lasted so far, (fingers crossed!! )
Note, when I bought the boat, I changed the rotor when I found some pitting on the seal-face. That was 13 yrs. ago.
 
Dave, you might care to note that PSS are (or were when I had one) emphatic that the grub screws should be replaced with new. There are four in total, two in each hole. As earlybird suggests, PSS' own instructions on installing the entire seal system new should tell you all you need.

A hose clip clamped to the shaft ahead of the rotor with the bellows compressed effectively gives you an 'extra hand' during installation. There's no reason I can think of that such a clip can't be left on the shaft as an added security measure, save for the possibility of encouraging a bit of corrosion.
 
Good point about grub-screws. I think that I ordered them with the bellows, cost pennies if I remember. Having said that, the basic reason for new ones is probably, IIRC, that they come pre-coated with thread locking compound, so a low/medium strength Loctite should be OK with the old ones, but easier to buy new. I also fitted new O-rings, again pence, unlike the new bellows!
 
When fitting and refitting the PSS shaft seal on my boat I, like "earlybird" in post 2, found compressing the bellows was the biggest challenge. I needed considerable leverage to provide the required pressure - much more than I could easily apply.

The issue was finding a way to provide a firm, fixed base against which I could lever (not much space around he shaft on my boat). I also wanted to be able to increase the pressure, if that proved necessary, once the boat was back in the water so the tools and materials used had to be those carried on the boat. Eventually I went for a set of shaped wood blocks and spacers that sat over the shaft between the coupling and the rotor. There are probably lots of ways of doing it and many better than this but this one worked/works for me.

The principal is to gradually increase the number of spacers (thin plywood) as I lever the rotor down the shaft, bit by bit. In my boat achieving adequate compression requires the application of considerable force - not on the PSS parts (except as designed) but on the wooden blocks and spacers. A hammer is used to tap the spacers in and a large spanner used as a lever. No leverage is applied directly to the rotor - only to the wooden block bearing on it. The forces involved mean the spacers are usually broken by the time the job is finished.

Whichever way you end up doing it, I hope it goes well.
 
Thanks for the replies, they make sense. I have studied the bottom video in my first post. So the first part of the job is to dismantle the "shaft coupling" (wot fixes the shaft to the gear box :). Then do the shaft seal job slipping everything forward off the end of the shaft and reassembling (with the appropriate new bellows, O rings,grub screws and cleaning the shaft). Then reconnect shaft to gearbox. Reckon I can do it! Aquafax look like the dealers for the UK.
 
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