1/2 seacock

Jun 11, 2004
1,621
Oday 31 Redondo Beach
Does anybody besides Forespar Marelon make a 1/2" flanged seacock?
Or a 1/2" flanged adaptor base like Groco makes for 3/4" and up?

Can't seem to find any 1/2 bronze seacocks.

Thanks
 
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
1) Just use a Marelon seacock. It has advantages over the metal ones. Use the "OEM" integrated style - way tougher than their traditional design. The 3/4" size is much more practical than the 70's era small one that plugged too easily.
2) If you go with bronze, change to the 3/4" size. If using metal thru hulls, be very careful to avoid stray current @ your moorage.
3) If this is for the engine intake, and you do not already have a strainer, install one.

Fair winds!
 

capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
There's little reason to use a ½" seacock. It will plug up much more easily and any growth in it will reduce the flow to nil. Install the 3/4 and reduce it somewhere in the line. That's why almost nobody makes one.
 
Jun 11, 2004
1,621
Oday 31 Redondo Beach
There's little reason to use a ½" seacock. It will plug up much more easily and any growth in it will reduce the flow to nil. Install the 3/4 and reduce it somewhere in the line. That's why almost nobody makes one.
It's been a 1/2" thru hull for 32 years with no problems and I don't really want to enlarge the existing hole in the boat.

It originally came with a thru hull with a ball valve on it, not a real seacock. The backing plate is rotting out so I have to work on it and was wanting to replace it with a true seacock. So I guess i'll either go with the Marelon seacock or just stick with the thru hull and ball valve unless I can find a 1/2" bronze seacock.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
You will find very little in the way of bronze seacocks or thru-hulls, in 1/2" or smaller, because they don't meet the ABYC strength standards, and manufacturers don't want that liability.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
It's been a 1/2" thru hull ...or just stick with the thru hull and ball valve unless I can find a 1/2" bronze seacock.
Nothing wrong with a thru hull and ball. My Benny came with nothing but. If you have a Beneteau dealer near you, they may have the small setup that feeds water to the prop shaft. Maybe someone on here had changed theirs and can advise?
 
Jun 11, 2004
1,621
Oday 31 Redondo Beach
You will find very little in the way of bronze seacocks or thru-hulls, in 1/2" or smaller, because they don't meet the ABYC strength standards, and manufacturers don't want that liability.
The guy at Forespar implied that their 1/2' Marelon seacock met the standard. Do you think he was stretching reality?
Would you suggest just going with a bronze thru hull and ball valve. If I went with that I would of course get a thru hull with combination NPS/NPT threading.

Thanks
 

capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
The guy at Forespar implied that their 1/2' Marelon seacock met the standard. Do you think he was stretching reality?
Would you suggest just going with a bronze thru hull and ball valve. If I went with that I would of course get a thru hull with combination NPS/NPT threading.

Thanks
I don't use ball valves on under water thru hulls. I only use proper marine bronze seacocks. I guess it's a personal choice, but I'm not building boats on a production line with a bottom line to worry about.
 
Nov 26, 2008
1,966
Endeavour 42 Cruisin
From Forespar..."Today Marelon® plumbing is now used by custom builders such as Wally Yachts, Oyster, Swan, Baltic, Morris and many other production builders such as Wellcraft, Boston Whaler, Sabre, Godfrey, Triton, Hinkley, S-2, Baja, Cobalt, and more than 100 others, power and sail. "