I'm interested in others' experiences in pump rebuilds.

I just rebuilt (seal and impeller) a Johnson pump that had started to leak
.. "Just in case", I bought a new pump as a spare (Mack Boring said they
didn't fool with repair if one leaked, only impeller replacement), and sure
enough, before I installed the pump, I decided to replace it because it
didn't rotate smoothly.

Now a couple of months later I got around to taking the old apart to figure
what the problem. The bearing is frozen, presumably from seawater leaking on
it.

Since I've not had an impeller to fail, I'm thinking it is more important to
replace the seal every couple of years, and while at it, go on and replace
the impeller. Got to protect that bearing.

What do you think ?