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Mark Borgerson

In article , says...

Greetings, all you thinkers...

I have an apparently immobile center-remains of an intermediate drive shaft
bearing which has resisted all my efforts so far to get it to slide up the
shaft.

I'll skip the gory details of how we got to this point other than to say it
must come off if I am to remove the shaft for shortening and checking for
straight, redoing the cutlass bearing, and so on. The need for shortening
was shooting myself in the foot when I replaced the shaft as we bought it
(pitted, scored, and I wanted more length) by making it too long and thus
having too much beyond the cutlass bearing, allowing enough movement out
there to cause whip in the middle of the 9'+ shaft, and thus the
installation of an intermediate bearing.

That it didn't have, or, I expect, need one (or the extremely anal surveyor
would have commented on it during our sea trial), suggests that shortening
it to the minimum possible (along with the newly rebuilt - and thus
balanced - Maxprop) will make that feature unneeded.

In any event, the picture gallery is the Maxprop - Shaft - Bearing folio in
the 2011 refit section of my gallery linked below, if you care to see what's
happened so far.

I got the setscrews out after long periods of soaking and trying and
banging, but all my efforts at getting it to slide up the shaft, so far,
have been for naught.

That is, except for what I assume must be SOME movement, as, before I
thought far enough ahead about the potential for dings, I whacked it with a
long, BIG screwdriver (the only suitable - as much as it WASN'T really
suitable - driver I had to hand) without protecting the shaft. Looking
closely, I see a half-dozen or so closely-spaced nicks which I presume were
the screwdriver's fault (well, mine, of course!), and perhaps a quarter-inch
of blank space (presumed gained when I quit putting the screwdriver on the
shaft!). This leads me to believe that I have, in fact moved it slightly,
but no further.

Why NOT no further doesn't compute, as there's nothing up the shaft which
would have the mass or chops to impede its sliding - and, certainly, it
won't move back down the shaft (or, at least, I don't have the access to
whack it from the other direction, and its currently immobile condition
suggests I'd not be able to move it by hand).

I've tried heating it, but I don't have anything which can inject massive
amounts of heat quickly, so that's probably the reason it didn't help. I've
anti-seized it to death, with no apparent difference, despite my seeing that
it appears to run through relatively easily (seep down from up to down
angle, setscrew holes filled, then emptying over time).

My 10-years internet buddy, recently ex- of this yard, who's faced most of
the challenges I have, tells me to cut it off with a cutoff in my angle
grinder as he did with his. As I don't want to accidentally involve my
shaft, I've not done that, but am approaching the point where I measure the
height of the bearing and mark my cutoff wheel to a depth slightly less than
that (becoming even more less as the material is worn off in cutting), and
have at it. Certainly, cutting off the housing and the race worked
adequately. But I'd rather just slide it up.

Any other ideas?

This is the kind of problem I've solved in the past with a Dremel tool
and cutoff wheels. Two diametrically opposite cuts through the bearing
and you remove the two halves of the bearing. If you've moved the
bearing past the part of the shaft where the new one will have to seat,
so much the better. You will have to be less careful of scoring the
shaft itself.

It may take a full package of the cutoff wheels. They are fairly
fragile. But they are not terribly expensive, either.

Mark Borgerson