They haven't. I replaced all mine on an '85 Krogen and the new ones fit
exactly.

I did replace a bunch of those old rubber plug type seacocks, and readily
sold them on E-bay to folks who needed them for replacement parts!

We ended up using an angle grinder to just grind off the exterior mushroom
part of some of the thru-hull fittings to get them out. If you have a cored
hull, that is a good time to make sure the coring has been routed out for an
inch or so and filled with epoxy. If not, do it now. As the original poster
stated, old bedding compound can (will) fail eventually. If you have one
with 5200, it obviously was installed relatively recently. They do have
something called anti-bond 2000 that will soften that stuff up as well.

--


Keith
__
"I'll always be Number 1 to myself."
-Moses Malone
"Roger Long" wrote in message
...
Old thru-hulls are not made any more, so get the
West System brochure...you'll need it to learn how to plug old
thru-hull holes and drill new ones.


Yikes! Please tell us more about this. These things are supposed to be
NPT and NPS standard. I see fittings in the store that look just like
I've been seeing for 40 years.

What changed and when?

How could they have changed so much that you can't put a new one back in
the same hole, even if the size is slightly different?

--

Roger Long