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HK

Hans Knoepfel

Thu, Jan 2, 2020 3:17 PM

A well established boat yard in Jacksonville recently replaced a thru-hull valve which was stuck.
The ball valve has been secured in place against the hull with 3 stainless steel bolts, replacing the original bronze bolts.

Question: are the SS bolts a no-no or acceptable in this case.

Hans Knoepfel
Mischief, a 42’ Hatteras LRC

Sent from my iPad

A well established boat yard in Jacksonville recently replaced a thru-hull valve which was stuck. The ball valve has been secured in place against the hull with 3 stainless steel bolts, replacing the original bronze bolts. Question: are the SS bolts a no-no or acceptable in this case. Hans Knoepfel Mischief, a 42’ Hatteras LRC Sent from my iPad

RS

Rudy Sechez

Thu, Jan 2, 2020 4:39 PM

Great question Hans. I'd prefer bronze. Stainless steel, when deprived of
oxygen as it is where it goes through the hull, will develop corrosion
problems, which when that magical point is reached to weaken the bolt
sufficiently will allow it to fail. The big question is when, and
unfortunately that cannot be established since the 'bad' part of the bolt
is buried, and even if it was observable, some of the deterioration will
still remain unobservable.
A point of interest, if it is a seacock, and it should be if it is below
the healed waterline, assembled tightly to the thru-hull provides
sufficient strength, enough to satisfy ABYC standards. I've been told by
several of the seacock manufacturers, the bolts through the seacock's base
are placed there to eliminate twisting when the valve is opened or closed,
particularly if the valve is hard to operate.

Rudy & Jill Sechez
*BRINEY BUG-a 34' Sail-Assisted Trawler *
Anchoring Consultants @ trawlertrainingabc.com
http://trawlertrainingabc.com
850-832-7748
Cocoa FL

Great question Hans. I'd prefer bronze. Stainless steel, when deprived of oxygen as it is where it goes through the hull, will develop corrosion problems, which when that magical point is reached to weaken the bolt sufficiently will allow it to fail. The big question is when, and unfortunately that cannot be established since the 'bad' part of the bolt is buried, and even if it was observable, some of the deterioration will still remain unobservable. A point of interest, if it is a seacock, and it should be if it is below the healed waterline, assembled tightly to the thru-hull provides sufficient strength, enough to satisfy ABYC standards. I've been told by several of the seacock manufacturers, the bolts through the seacock's base are placed there to eliminate twisting when the valve is opened or closed, particularly if the valve is hard to operate. *Rudy & Jill Sechez* *BRINEY BUG-a 34' Sail-Assisted Trawler * *Anchoring Consultants @ trawlertrainingabc.com <http://trawlertrainingabc.com>* *850-832-7748* Cocoa FL

L

LAL

Thu, Jan 2, 2020 5:08 PM

You have a LRC. That boat is NOT a spring chicken. If the bronze bolts are
from new construction, I would stay with bronze bolts. Why mess with
success?

When I have work done, the yard knows that it is a like for like
replacement, unless there is a significant amount of conversation between
me and them.

They do not like the conversation. They always do like for like, even if
that means off to a machine shop to make an exact duplicate. (Which BTW
they just did because their solution was a half-ass one.)

Lee

LeeZe

Levent Marina, Izmir Turkey

On Thu, Jan 2, 2020 at 6:18 PM Hans wrote:

A well established boat yard in Jacksonville recently replaced a thru-hull
valve which was stuck.
The ball valve has been secured in place against the hull with 3 stainless
steel bolts, replacing the original bronze bolts.

You have a LRC. That boat is NOT a spring chicken. If the bronze bolts are from new construction, I would stay with bronze bolts. Why mess with success? When I have work done, the yard knows that it is a like for like replacement, unless there is a significant amount of conversation between me and them. They do not like the conversation. They always do like for like, even if that means off to a machine shop to make an exact duplicate. (Which BTW they just did because their solution was a half-ass one.) Lee LeeZe Levent Marina, Izmir Turkey On Thu, Jan 2, 2020 at 6:18 PM Hans wrote: > A well established boat yard in Jacksonville recently replaced a thru-hull > valve which was stuck. > The ball valve has been secured in place against the hull with 3 stainless > steel bolts, replacing the original bronze bolts. >

trawlers@lists.trawlering.com

Correct bolts in a thru-hull mounting