Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 06-05-2018, 19:54   #1
Registered User

Join Date: Feb 2008
Boat: Beneteau 411
Posts: 164
Replace this seackock & thru hull, right?

Here's a picture of seacock on my new boat (new to me - it's 19 years old).

It seems neither I nor my surveyor looked very closely at the seacocks.

This looks like something that needs to be replaced not just cleaned up would you say?

Also, it looks like mixed metals are being used which I believe should be avoided?
Attached Thumbnails
Click image for larger version

Name:	20180506_153845.jpg
Views:	631
Size:	415.0 KB
ID:	169315  
__________________

__________________
A good traveler has no fixed plans
and is not intent upon arriving -Lao Tse
sgtPluck is offline   Reply With Quote
Old 07-05-2018, 08:47   #2
Registered User

Join Date: Nov 2012
Posts: 194
Re: Replace this seackock & thru hull, right?

Quote:
Originally Posted by sgtPluck View Post
Here's a picture of seacock on my new boat (new to me - it's 19 years old).

It seems neither I nor my surveyor looked very closely at the seacocks.

This looks like something that needs to be replaced not just cleaned up would you say?

Also, it looks like mixed metals are being used which I believe should be avoided?
The white deposits could be salt from a loose hose fitting, or it could be zinc oxide. If it is zinc oxide, one of the fittings is brass not bronze. By the look of it, the hose nipple could be brass, not bronze, but it is difficult to tell from the picture. The only way to tell is remove the hose and clean up the fittings. Brass dezincifies and all that is left is a copper sponge, which has no strength. It should be clear once the hose is removed.
__________________

Pitchondesign is offline   Reply With Quote
Old 07-05-2018, 08:53   #3
Registered User

Join Date: Nov 2012
Posts: 194
Re: Replace this seackock & thru hull, right?

Quote:
Originally Posted by Pitchondesign View Post
The white deposits could be salt from a loose hose fitting, or it could be zinc oxide. If it is zinc oxide, one of the fittings is brass not bronze. By the look of it, the hose nipple could be brass, not bronze, but it is difficult to tell from the picture. The only way to tell is remove the hose and clean up the fittings. Brass dezincifies and all that is left is a copper sponge, which has no strength. It should be clear once the hose is removed.
Taking a second look at the picture, the color of the valve is much lighter than the angle fitting. Bronze is darker in color than brass. It might be the valve is also brass. Bronze is an alloy of copper and tin, brass is copper and zinc, in innumerable variations.
Pitchondesign is offline   Reply With Quote
Old 07-05-2018, 09:15   #4
Registered User
 
Terra Nova's Avatar

Join Date: Apr 2007
Location: Marina del Rey, California
Boat: Mako 248
Posts: 4,089
Re: Replace this seackock & thru hull, right?

Replace it with a real sea cock, not a ball valve.
__________________
1st rule of yachting: When a collision is unavoidable, aim for something cheap.
"whatever spare parts you bring, you'll never need"--goboatingnow
"Id rather drown than have computers take over my life."--d design
Terra Nova is offline   Reply With Quote
Old 07-05-2018, 09:27   #5
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29° 49.16’ N 82° 25.82’ W
Boat: Pearson 422
Posts: 13,743
Re: Replace this seackock & thru hull, right?

First determine if any of the parts are brass instead of bronze. Brass can deteriorate quickly, break off and sink your boat.

Then add a backing place or flange to support the thru-hull. From the photo is looks like the elbow is screwed directly to the threaded end of the thru-hull mushroom which then has no support if force is applied to the elbow as in trying to free a stuck valve, dropped tool box or whatever.
__________________
The water is always bluer on the other side of the ocean.

Sometimes it's necessary to state the obvious for the benefit of the oblivious.

Rust is the poor man's Loctite.
skipmac is offline   Reply With Quote
Old 08-05-2018, 08:33   #6
Registered User
 
S/V Alchemy's Avatar

Join Date: May 2008
Location: Toronto
Boat: Custom 41' Steel Pilothouse Cutter
Posts: 4,949
Re: Replace this seackock & thru hull, right?

Generally, if you are self-prompted to ask, the answer is "yes". I agree with all the other suggestions above.
__________________
Can't sleep? Read www.alchemy2009.blogspot.com for fast relief. Can't read? Avoid www.volumesofsalt.blogspot.com, because it's just personal reviews of sea books.
S/V Alchemy is offline   Reply With Quote
Old 08-05-2018, 08:46   #7
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 21,127
Re: Replace this seackock & thru hull, right?

The colors of the pieces might bother me. that's likely just a commercial hardware store ball valve. They last a few years but it should be replaced.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is offline   Reply With Quote
Old 08-05-2018, 08:58   #8
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: The boat: Cowes (Winter), Above 60N (Summer); me: somewhere in the air!
Boat: Cutter-Rigged Moody 54
Posts: 23,811
Re: Replace this seackock & thru hull, right?

Quote:
Originally Posted by Cheechako View Post
The colors of the pieces might bother me. that's likely just a commercial hardware store ball valve. They last a few years but it should be replaced.
Indeed.

That ball valve looks like chromed brass hardware store stuff -- get rid of it.

It's hard to say whether the other hardware is any good or not, and that's a good reason to replace it all. Moreover, it's important that all underwater fittings in contact with each other be made of the same material so that unlike metal corrosion doesn't happen.

So rip it all out and replace it.

As to what to replace it WITH -- I've had bad luck with DZR Brass -- others may have a different opinion. My boat was built with gunmetal bronze underwater fittings, and that's what I'm replacing the originals with, gradually. It has held up well, but the Guido brand ball valves had mild steel handles which have rusted like yours have. I'm now using Maestrini ball valves and fittings which have stainless handles.

Don't do what I did and replace them gradually -- at that age, it's best to just do all of them in one fell swoop, including the skin fittings.
__________________
"Parce que je suis heureux en mer, et peut-ętre pour sauver mon ame. . . "
Dockhead is online now   Reply With Quote
Old 08-05-2018, 09:06   #9
Registered User
 
Scout 30's Avatar

Join Date: Oct 2014
Location: Florida
Boat: Scout 30
Posts: 3,006
Re: Replace this seackock & thru hull, right?

A proper seacock should be attached directly to the thru hull and bolted to a backing plate or through bolted through the backing plate & hull. If an elbow is necessary it should be bronze & attach to the other side of the seacock unless there is no clearance for the seacock which is not the case here.

Replacing Thru-Hulls and Seacocks Photo Gallery by Compass Marine How To at pbase.com
Installing A Seacock & Thru-Hull Fitting In A New Location Photo Gallery by Compass Marine How To at pbase.com
Scout 30 is offline   Reply With Quote
Old 08-05-2018, 09:15   #10
Registered User

Join Date: May 2016
Location: Hobart, Tasmania
Boat: Adams 12
Posts: 10
Re: Replace this seackock & thru hull, right?

A friend had one of those 'non-marine' ball valves on his boat and one day the handle was a little stiff but instead of the valve opening the whole thing snapped off in his hand. It looked fine on the outside but had corroded badly on the inside and resulted in almost no wall thickness to the valve body material which is why it failed.
I've replaced my seacocks with a composite 'marine grade' product by a NZ company called Trudesign. I'm very happy with them. They have a number of industry certifications, have no metallic components and operate very smoothly. Not worth sinking your boat just to save a few bucks; keep the garden fittings for the garden!
cjheath is offline   Reply With Quote
Old 08-05-2018, 10:34   #11
Registered User
 
CarinaPDX's Avatar

Join Date: Jan 2010
Location: Portland, Oregon, USA
Boat: 31' Cape George Cutter
Posts: 2,085
Re: Replace this seackock & thru hull, right?

I'll take a bit of a contrarian postition. While this installation is not remotely best practice, beyond the rusting handle I see no reason to panic. The valve is almost certainly plated bronze, not brass, and the thru-hull and elbow are also bronze. For now the one thing to do is either clean/paint the handle, or track down a stainless steel handle. It wouldn't be a bad idea to track down the valve specs just to be certain, but if it were brass there would likely be a lot bigger mess.

Long term it would be a good idea to upgrade the whole assembly, at one time. Either install a seacock with integral flange to the hull, or install a valve with separate Groco flange (the current install appears to mate a tapered thread elbow with a straight thread thru-hull - neither strong nor leak-resistant). The elbow should be between the valve and hose barb, not the valve and thru-hull, and probably isn't needed if you replace the hose with a longer piece; otherwise consider an angled hose barb. (I consider old hoses more of a threat than your seacock arrangement.)

Some argue that the traditional "tapered" seacocks are the way to go, but modern ball valves can function for decades reliably (as has been my experience) and don't require as much maintenance. Do be careful to get one with a stainless or bronze handle, and made of bronze, not brass, which isn't likely a problem but definitely should be confirmed. I am more distrustful of smaller valves - I had a 3/4" fail once when the shaft parted company with the ball - it corroded apart but the seal around the shaft held it together and provided resistance to turning, so it seemed it was working when it wasn't. Seacocks are not the place to save money...

Greg
CarinaPDX is online now   Reply With Quote
Old 08-05-2018, 10:47   #12
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: The boat: Cowes (Winter), Above 60N (Summer); me: somewhere in the air!
Boat: Cutter-Rigged Moody 54
Posts: 23,811
Re: Replace this seackock & thru hull, right?

Quote:
Originally Posted by CarinaPDX View Post
I'll take a bit of a contrarian postition. While this installation is not remotely best practice, beyond the rusting handle I see no reason to panic. The valve is almost certainly plated bronze, not brass, and the thru-hull and elbow are also bronze. For now the one thing to do is either clean/paint the handle, or track down a stainless steel handle. It wouldn't be a bad idea to track down the valve specs just to be certain, but if it were brass there would likely be a lot bigger mess.

Long term it would be a good idea to upgrade the whole assembly, at one time. Either install a seacock with integral flange to the hull, or install a valve with separate Groco flange (the current install appears to mate a tapered thread elbow with a straight thread thru-hull - neither strong nor leak-resistant). The elbow should be between the valve and hose barb, not the valve and thru-hull, and probably isn't needed if you replace the hose with a longer piece; otherwise consider an angled hose barb. (I consider old hoses more of a threat than your seacock arrangement.)

Some argue that the traditional "tapered" seacocks are the way to go, but modern ball valves can function for decades reliably (as has been my experience) and don't require as much maintenance. Do be careful to get one with a stainless or bronze handle, and made of bronze, not brass, which isn't likely a problem but definitely should be confirmed. I am more distrustful of smaller valves - I had a 3/4" fail once when the shaft parted company with the ball - it corroded apart but the seal around the shaft held it together and provided resistance to turning, so it seemed it was working when it wasn't. Seacocks are not the place to save money...

Greg
Have you ever seen or even heard about a plated BRONZE ball valve? I have not. I'm not saying they don't exist -- I don't know that -- but I've never heard of it, and I got 0 hits on Google.

I suspect the first diagnosis was correct -- that this is carp Home Depot plated plain brass, which really should be tossed out with prejudice. But I will be happy to have my knowledge expanded if there is such a thing which I've never heard of.


As to your advice about handles -- I agree wholeheartedly. Plain steel handles don't belong on such hardware at all.
__________________
"Parce que je suis heureux en mer, et peut-ętre pour sauver mon ame. . . "
Dockhead is online now   Reply With Quote
Old 08-05-2018, 11:43   #13
Registered User
 
CarinaPDX's Avatar

Join Date: Jan 2010
Location: Portland, Oregon, USA
Boat: 31' Cape George Cutter
Posts: 2,085
Re: Replace this seackock & thru hull, right?

What I can tell you is that I bought four 1-1/2" plated ball valves when I did a blister job in Turkey, 12 years ago, and they look similar to the OP's valve. I was told that they were bronze, and experience has given me no reason to doubt that. Bronze usually develops a green or brown layer of corrosion, then stops and is stable for millenia. These valves (mine and the OP's) have developed a little green corrosion where the plating has come off, but haven't continued to eat into the underlying metal. Brass would show deeper corrosion, and often exhibits a tell-tale pink look. This is not a sure-fire test, and doesn't reflect what may be happening inside the valve (e.g. my corroding stem) - but in this case doesn't set off alarm bells either.

My point is that I don't see any reason to be immediately concerned, although a certain amount of vigilance is called for (well, always really). OTOH there is less than certainty about the provenance of the valve, and the assembly has other issues, so it would be best to upgrade at some point. Valves aren't that expensive, so when the reconfigure is done it doesn't make sense to use anything but known quality valves.

Personally I am preparing to install Groco flanges, to bring things up to best practice. I will be replacing the head exhaust valve because I want one I can easily lock, and which has a non-corrosive handle. I will be re-installing an old valve in the galley, after replacing the handle with a stainless one. So two of the plated valves will be out. I am reusing the other two and will be painting the handles (I haven't found a source for compatible SS handles) - they are very near the waterline on the cockpit drains so less critical. I will be carefully scrutinizing them though, and anything out of the ordinary and they will be gone.

Greg
CarinaPDX is online now   Reply With Quote
Old 08-05-2018, 12:38   #14
Registered User

Join Date: Jun 2015
Posts: 16
Re: Replace this seackock & thru hull, right?

The MS58 cast into the part is a designation for a grade of brass CuZn39Pb
MonkeyButler is offline   Reply With Quote
Old 08-05-2018, 14:02   #15
Registered User

Join Date: Mar 2015
Location: New Zealand
Boat: Moana 33
Posts: 1,092
Re: Replace this seackock & thru hull, right?

From that excellent article posted by Scout 30 above (post #9) it seems there may be some argument for keeping the thru-hull (mushroom) and replacing everything else. That would be so easy to do (not even requiring a haul-out, if you use one of those little plastic umbrella things to stop the flow temporarily, or just get wet and pop the bung in from the outside). I can certainly see some merit in keeping that single-hole thru-hull instead of replacing with a bronze flange fitting plus requisite large grp internal doubler and three extra bolt holes. (Geeze if that hull is cored then the extra bolt holes, if they miss the portion of solid hull around the fitting, could spell disaster!) Provided the mushroom is located in a well-protected location, as mentioned in the comment to Scout's article, there isn't necessarily much wrong with the existing bronze thru-hull.

If he did decide to keep the bronze thru-hull but replace the brass valve (and of course toss that silly elbow), how do we ensure pipe threads are compatible? I'm faced with similar dilemma so any advice welcome, especially if it makes things less costly.
__________________

NevisDog is offline   Reply With Quote
Reply

Tags
hull, thru hull

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Thru-hull transducer mounting in steep deadrise hull Robertkwfl Marine Electronics 1 01-11-2016 13:59
Fitting thru hull to uneven hull zboss Construction, Maintenance & Refit 12 16-09-2013 06:54
Exhaust: Thru Hull? Not Thru Hull? steel Powered Boats 12 18-10-2012 21:14
Replace depth transducer cored hull - r&r thru with in hull? rpeebles Marine Electronics 5 11-04-2012 11:58
Garmin 'In-Hull' vs 'Thru-Hull' Transducers La Bras D'or Navigation 24 23-09-2009 07:26



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 01:49.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.