Wow. Live and learn. I have no clue what a plug valve is, but I like
the sound of it. Off to Google I go.

R.


On Thu, 08 Jan 2004 12:44:16 -0500, DSK wrote:

Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief benefits is
that you can disassemble them without taking apart the piping, something that
can't be done with ball valves. Also, if they happen to freeze up, they are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat last
spring, and couldn't find any that we could actually get in time. However, at
some boatyard session in the not-too-distant future I have to replace (upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

I don't think they even make those any more, do they? I know I had a willing
buyer for a set that I replaced on my Krogen with Groco seacocks.

"DSK" wrote in message
...
Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug
valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief
benefits is
that you can disassemble them without taking apart the piping, something
that
can't be done with ball valves. Also, if they happen to freeze up, they
are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat
last
spring, and couldn't find any that we could actually get in time. However,
at
some boatyard session in the not-too-distant future I have to replace
(upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

I don't think they even make those any more, do they? I know I had a willing
buyer for a set that I replaced on my Krogen with Groco seacocks.

"DSK" wrote in message
...
Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug
valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief
benefits is
that you can disassemble them without taking apart the piping, something
that
can't be done with ball valves. Also, if they happen to freeze up, they
are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat
last
spring, and couldn't find any that we could actually get in time. However,
at
some boatyard session in the not-too-distant future I have to replace
(upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

Doug,

Try Spartan marine. They make bronze seacocks for Cape Dory/Robinhood Yachts.

Larry Demers

DSK wrote:

Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief benefits is
that you can disassemble them without taking apart the piping, something that
can't be done with ball valves. Also, if they happen to freeze up, they are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat last
spring, and couldn't find any that we could actually get in time. However, at
some boatyard session in the not-too-distant future I have to replace (upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

Doug,

Try Spartan marine. They make bronze seacocks for Cape Dory/Robinhood Yachts.

Larry Demers

DSK wrote:

Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief benefits is
that you can disassemble them without taking apart the piping, something that
can't be done with ball valves. Also, if they happen to freeze up, they are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat last
spring, and couldn't find any that we could actually get in time. However, at
some boatyard session in the not-too-distant future I have to replace (upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

Steve wrote:

As others have stated, Gate Valve are not suited for marine use and
especially for below the waterline.

However, IMHO, the plug valve is superior to the ball valve. The plug valve
can be taken apart and cleaned or repaired. It seems that they would be
cheaper to manufacture as well..

Agreed. Good plug valves are hard to find, though. One of the chief benefits is
that you can disassemble them without taking apart the piping, something that
can't be done with ball valves. Also, if they happen to freeze up, they are
easier to unfreeze.

I looked all over for plug valves to replace some seacocks on our boat last
spring, and couldn't find any that we could actually get in time. However, at
some boatyard session in the not-too-distant future I have to replace (upsize)
two seacocks and intend to have plug valves on hand for that job.

Fresh Breezes- Doug King

A proper sea cock, in the strictest sense (was) a tapered plug valve with a
flange on the outboard side and internal threads for the throught hull.. The
flange would be bolted though to the outside with a fitted block on the
inside. The through hull was just that and provide little or no structural
strength the the installation..

Pipe threads and none tapered through hull threads are weak because of the
amount of base metal that is removed during the threading process.

Today, you will seldom find a true and proper sea cock. What you will find
is a through hull with a valve threaded on the end of the inboard end of the
threads.. Even this is not a proper installation because the threads in the
standard valve will be tapered while the through hull threads are straight..
When tightened up, only the first couple threads will be holding the
pressure and providing mechanical strength.

There is often the recommendation that you try standing on your through hull
valve to ensure that the through hull is still sound.. That may be an
indication of strength of the exposed threads, however straight threads into
a tapered valve thread really leads to a valve that could easily vibrate or
be accidently loosened.

Myself, I'm using the Forespar Marelon flanged Seacocks, with Marelon
through hulls.. (objective is to have all non-metalic/non-conductive
fittings below the waterline)

The flange bolts were a problem so I used flat head machine screws and
counter sunk the heads and epoxyed over them to prevent contact with the
water. I will have to keep an eye on these over time to see if there is any
evidence of water intrusion..


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

"Steve" wrote in message
...

Myself, I'm using the Forespar Marelon flanged Seacocks,
with Marelon
through hulls.. (objective is to have all
non-metalic/non-conductive
fittings below the waterline)

The flange bolts were a problem so I used flat head
machine screws and
counter sunk the heads and epoxyed over them to prevent
contact with the
water. I will have to keep an eye on these over time to
see if there is any
evidence of water intrusion..

Steve,
Are your machine screws stainless or other metal? If
stainless, keep an eye out for corrosion under the epoxy.
Stainless doesn't like to be deprived of oxygen, as you
know!

--
JimB
Yacht Rapaz, sadly for sale:

http://homepage.ntlworld.com/jim.bae...cification.htm
jim(dot)baerselman(at)ntlworld(dot)com

"JimB" wrote in message
...

Are your machine screws stainless or other metal? If
stainless, keep an eye out for corrosion under the epoxy.
Stainless doesn't like to be deprived of oxygen, as you
know!


I managed to find monel bolts for these sea cock flanges. ( I only have two
sea cocks that are below the waterline. Engine room cooling water and head
discharge.)

Steve

"JimB" wrote in message
...

Are your machine screws stainless or other metal? If
stainless, keep an eye out for corrosion under the epoxy.
Stainless doesn't like to be deprived of oxygen, as you
know!


I managed to find monel bolts for these sea cock flanges. ( I only have two
sea cocks that are below the waterline. Engine room cooling water and head
discharge.)

Steve