"Roger Long" wrote in message
...

A bronze cap of the same material and schedule will be just as
reliable as the thru hull which is a no back up component. Filling
the space with something resilient and flexible will exclude water and
also serve as a plug. I'd much rather depend on this with the thru
hull and inner nut sandwiching the glass that grinding back the hull
structure and depending on secondary glass bonds.

I would just leave the seacocks as you suggest except that they are
gate valves that I'm replacing and relocating at the same time.

--

Roger Long

Roger,

I agree with the other posters. If you read about boats sinking, it's
seldom from secondary bonds popping off. More often than not it is a
seacock failing in some way. I figure you have a number of failure
points with a capped off seacock (cap coming loose, corrosion of
thru-hull, long term failure of caulking (like in 10 years).

I would go so far as to say it would not pass a survey with just a cap
on thru hull.

Evan Gatehouse