Hi Jim,

...but presuming it was the PSS seal from PYI, the likely failure was the collar sliding forward on the shaft...

As you point out, there is absolutely no excuse whatsoever for that to ever happen... There are several ways to prevent it, of which yours is a good one... I've inserted a split section of PVC conduit on the short length of shaft between mine, and my shaft coupling...

It amazes me that everyone who uses the PSS doesn't do something similar, it's the easiest fix in the world... However, what is even more amazing, is that PYI doesn't recommend or insist upon it, in their installation instructions... (Although perhaps they do now, it's been years since I did mine)

I certainly think the fear that some have of a seal like the PSS is a bit unwarranted, I've never had a serious issue with one... Whereas I've had many issues with traditional stuffing boxes over the years, always makes me nervous getting aboard a boat where one is an unknown quantity, not knowing the 'history' of its service, how badly the shaft might be scored, etc... I'd sooner have a PSS seal on a boat unknown to me, every time...