Seacocks replace or service?

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Grahambda

Veteran Member
Joined
Oct 5, 2015
Messages
84
Location
Cayman Islands
Vessel Name
Bom Dia
Vessel Make
DeFever 44 OC
HI,

Our 1990 DeFever 44 is currently on the hard and we have done several projects. One major area that concerns me is the state of the seacocks (bolted through the seachest. I believe they are bronze (or brass, but unsure); there are nine of them, and two I won't need anymore - converting the heads from saltwater to fresh water, but leaving seven to deal with (2 x engines, 1 x gen set, 2 x A/C, 1 x Watermaker, 1 x refrigeration. Three of them are combo strainers/valves.

Other than the fact they are all very green due to the chemical reaction, which can be cleaned off, they are the old type t-handle, and all are difficult to open/close. Should I look to try and have these serviced or is it best to spend the many $$ on complete replacements? (combo strainers alone are in the $800.00 range - probably looking at around $5-6k for parts alone). If servicing, based on the attached photos any thoughts on where to buy the refurb kits? Thanks!

(BTW the yard manager who I asked to take a look at them suggested: "leave them as is, roll the dice and make sure you have plenty of wooden plugs on board!") - not very helpful.
 

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Greetings,
Mr. G. I'm a big fan of bronze (Never brass or shouldn't be brass) seacocks and fitments. The one's on our previous boat (Savasa) were original 1979 vintage. I did have them serviced shortly after we adopted her on or about 2009. From what I vaguely recall valves were "cleaned up" with grinding compound and appropriately greased. They were exercised regularly and re greased when necessary.
To prevent/minimize further verdigris I gave them a light coat of Fluid Film:


iu



https://www.fluid-film.com/
 
If it were my boat, I would replace them. I base my comment on looks and age and that I don't even want to think about actually having to use my emergency plugs.
 
I’d take that roll of the dice. You are dealing with a straight yard manager. If they open and close correctly after serving keep them. You have to go a long way to get a seacock to fail. The yard manager gave you good advice.
 
Those look to me like GROCO seacocks which means likely that the strainers are by the same Mfgr. which means they are high quality and BRONZE.

Brass would have fallen apart years ago.

THe greening means little other than they are green. A SS wire brush can lighten the green verdegris but other wise leave it be. THat green won't harm the T.H. other than appearance.


Unfortunately Groco no longer supplies the rubber plugs needed to repair the T.H.s so if they have deformed they MAY no longer be serviceable so they may need to be replaced. Some people have had success by LIGHT sanding of deformaties to smooth the operation.

Service means a BOAT out of water strip down leaving the body mounted, cleanup, inspection, water resistant greasing of the plug and interior seacock body and a new gasket.

Periodic greasing, in water, can be done with the installation of a SS grease nipple in one of the drain holes and a yearly single shot, not gobs,of the same/similar grease. Change the SS grease nipple every few years though.

THe sea strainers are likely good for many years yet although I believe the designs have been changed. Phone and ask about parts as they are likely still available.

By the way I replaced my Perko sea cocks unit sight glass many
years ago so even if they are no longer available as Groco parts they can be made successfully. Acrylic tube , 1/4 " thick wall and some machining.
I also used appropriate sized O rings.
 
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May have the solution

So I just spoke to an engineer at Groco that built those existing t-handle sea-cocks back in the late 80's, early 90's* - they are made by Groco, SV series (see data sheet below).
After a long chat with him, he recommended just "taking them apart, applying lots of silicon-based grease*and reassembling them, and they should last many more years" - he prefers them over the current ball valve models which tend to get clogged. If the rubber plug (item 4 in the sheet below) is cracked or*torn, then that's an issue as those can't be ordered anymore- then it's a replacement situation.

BTW he recommended DR-X rust remover to get that green oxidation off, so I will try that. Hope this helps others.
 

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I believe that the handle on the back needs to be loosened up to turn the shutoff handle. Maybe that is why they are hard to turn. Agree on taking them apart and see what condition the rubber plug is in. As said above if it is cracked or torn you will have to replace the seacock. But sometimes the plug takes a set where the hose is and swells up a bit into the pipe hole. You can lightly sand the swollen part a bit so it will turn easier. Then use a silicone grease, not petroleum based, and lube it up. Reassemble and see how it goes then. If it still doesn’t turn well then replace the seacock. But I wouldn’t just start by replacing all of them. Some, or all, of them may be fine after servicing them. Then spend the money on something else…
 
Greetings,
Mr. G. Just saw the newer posts. Our seacocks were all bronze (body and plug). I forgot about the rubber plugs being used. Follow, subsequent to my post (#2), "rubber plug" advice.
 
Get strong insurance... keep premium paid!
Emergency plugs... have a couple/few aboard.
Life vests... plenty
EPURB... charged
S to S... check it out before cruise / keep handy
Cell phone... might work, might not - depending where you are
Dink / life raft... with oars, motor preferred, sail works too!

That's my picture... for secure boat enjoyment. They are "Pleasure Boats"! :speed boat:

If it ain't broke or lookin/acting like a break is soon imminent - don't fix it!

Follow yard manager's recommendation - that's mine too!!! :dance:
 
If I might ask a question to gain some knowledge which is slightly off topic.

The marine enviroment is rather harsh.
Wouldn't a barrier coating of some type on those valves be prudent?

And yes I understand the real working is internal. Just wondering if the external part of the valve matters for it's integrity.

As a side note from the ignorant..... the yard manager said to do nothing. Since the vessel is out of the water for now, in my opinion, valve dissassembly and inspection seems prudent at this point. But what do I know?
 
Greetings,
Mr. A. "But what do I know?" You know enough to acknowledge that servicing should be done at this point.


iu



That's 4 thumbs up!
 
Greetings,
Mr. A. "But what do I know?" You know enough to acknowledge that servicing should be done at this point.


iu



That's 4 thumbs up!

I'm not even gonna ask for/from exactly what/why/where this body part is derived... owner alive to the rear??
 
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If I might ask a question to gain some knowledge which is slightly off topic.

The marine enviroment is rather harsh.
Wouldn't a barrier coating of some type on those valves be prudent?

And yes I understand the real working is internal. Just wondering if the external part of the valve matters for it's integrity.

As a side note from the ignorant..... the yard manager said to do nothing. Since the vessel is out of the water for now, in my opinion, valve dissassembly and inspection seems prudent at this point. But what do I know?


The verdegris is just surface discoloration. It doesn’t really hurt anything. I saw a new boat that the builder coated the bronze things with clear awlgrip. Looked nice but it was just for looks. I would pull the rubber bung and do what has been said above.
 
Graham, those seacocks are still viable. Remove the top keeper and pull the rubber plug out. You will find that there is a hump on what was once a cylinder. Lightly sand the humps so that they are cylindrical again. Reinstall with a compatible grease. They will last longer than your boat. If there is what looks like a drain plug, install a grease fitting in its place and inject grease occasionally. Search for "Old Groco Rubber Cone Seacocks" on this forum. You will get a lot of good info, and pictures. Same issue. I started that discussion for the same reason.
 
Groco Seacocks

As mentioned by previous poster, these are Groco Rubber Plug Seacocks. I have seven on our GB. I service mine every other year, very easy to do if you can access them. (And boat is on the hard) Back off wing bolt, remove two 1/4" bolts on the face plate and slide the rubber internal valve out. If there is any serious distortion or tears you can lightly sand with Emery cloth (can even run the Emery cloth around the interior of valve body to smooth up if needed) and as mentioned, coat interior of valve body and rubber plug with silicon grease. ...Clean up your face plate, bolts and star washers and reinstall. Quite simple and these valves are pretty bullet proof and simple. (Remember, before opening or closing these valves you need to back off wing bolt....and once opened or closed, tighten the wing bolt....This is what expands the rubber plug to block the open or closed ports)
When I first saw them, I thought these were a lost cause until I did an exploratory. Very easy!
Good luck!
Best
Mike Dana
Third Reef
36' Grand Banks Classic #819
Potts Harbor Maine (South Harpswell)
 
I would absolutely ditch the combo seacock-strainer, these will not pass the ABYC 500 Lb. 30 second test. I have personally experienced failures. The remainder of the seacocks can be disassembled, cleaned and placed back into service, they are fully rebuildable, but after all this time they don't owe you (or somebody) anything. As others have said the green verdigris isn't harmful. I am a fan of Groco products, but I never cared for the rubber bung style seacock. A Groco BV series seacock is robust and will likely outlast the boat, and certainly outlast your ownership.

On seacock in general https://stevedmarineconsulting.com/seacock-selection-service-and-avoiding-the-pitfalls-2/

Installation step by step https://stevedmarineconsulting.com/wp-content/uploads/2021/01/TaskSheet189-Closeouts-05.pdf
 
Those are great valves, you would not come close to the quality by replacing them.

They might need service including lapping them with grinding compound and then lubricating them.

BUT..keep them.

pete
 
I would absolutely ditch the combo seacock-strainer, these will not pass the ABYC 500 Lb. 30 second test. I have personally experienced failures. The remainder of the seacocks can be disassembled, cleaned and placed back into service, they are fully rebuildable, but after all this time they don't owe you (or somebody) anything. As others have said the green verdigris isn't harmful. I am a fan of Groco products, but I never cared for the rubber bung style seacock. A Groco BV series seacock is robust and will likely outlast the boat, and certainly outlast your ownership.

On seacock in general https://stevedmarineconsulting.com/seacock-selection-service-and-avoiding-the-pitfalls-2/

Installation step by step https://stevedmarineconsulting.com/wp-content/uploads/2021/01/TaskSheet189-Closeouts-05.pdf

Steve - Your input links are truly educational - Thanks, Art
 
Looked at hundreds and hundreds of Groco’s and rarely seen a problem. Easy to service don’t freeze up like Wilcox Crittenden or the English Davies and are made of good quality silicon bronze from same foundry that Buck Algonguin uses ( I’m told ). If the color freaks you out well it’s unwarranted. If they get pinkish in color then I’d worry a bit as this is sign of dezincafication but these are good quality with very little alloy zinc so not to worry. Hanging a sea strainer of that thru-hull is a a serious problem. Move it.

Surprised that nobody here has a problem boring four thru-hull holes in about a square foot of the underwater hull skin ? For years I’ve preached about the simplicity and common sense of a proper sea chest to builders here and abroad. Never got any traction ?

Rick
 
Surprised that nobody here has a problem boring four thru-hull holes in about a square foot of the underwater hull skin ? For years I’ve preached about the simplicity and common sense of a proper sea chest to builders here and abroad. Never got any traction ?

Rick

Where do you see that?

Not on the OP's vessel. That IS a sea chest!
 
Where do you see that?

Not on the OP's vessel. That IS a sea chest!

Good catch and my apology. I glanced at one photo on my phone and made a wrong guess and assumption. Just got home and looked at the third photo on my computer pretty friggin obvious. Oh well some days go better than others

Rick
 
Those are great valves, you would not come close to the quality by replacing them.

They might need service including lapping them with grinding compound and then lubricating them.

BUT..keep them.

pete

Respectfully disagree, the Groco BV series valves are, IMO, far superior. I always found it annoying to have to loosen the expansion screw on these rubber plug valves before turning them, in some cases reaching the valve handle is hard enough.

You can't really lap a rubber plug, you can lap a bronze on bronze cone-shaped valves.
 
Looked at hundreds and hundreds of Groco’s and rarely seen a problem. Easy to service don’t freeze up like Wilcox Crittenden or the English Davies and are made of good quality silicon bronze from same foundry that Buck Algonguin uses ( I’m told ). If the color freaks you out well it’s unwarranted. If they get pinkish in color then I’d worry a bit as this is sign of dezincafication but these are good quality with very little alloy zinc so not to worry. Hanging a sea strainer of that thru-hull is a a serious problem. Move it.

Rick
In this case, the sea strainer is integral with the valve, so it can't be moved per se, you'd need to change the valve. It should be removed and replaced with a separate seacock and strainer.
 
Respectfully disagree, the Groco BV series valves are, IMO, far superior. I always found it annoying to have to loosen the expansion screw on these rubber plug valves before turning them, in some cases reaching the valve handle is hard enough.

You can't really lap a rubber plug, you can lap a bronze on bronze cone-shaped valves.

Lap is not the correct term However I found that removing, cleaning, and sanding my 40 year old rubber Groco plugs worked fine. Reinstall with silicone grease. Certainly a better option than the expense of replacing seacocks for a slight improvement in functionality. Are the newer Groco seacocks an improvement? Absolutely. In my opinion not worth the expense unless absolutely necessary.
 
Steve I’m not sure I recall ever running into Groco’s strainer valve units like this. I must have seen them but don’t recall. I am curious though about load ratings per ABYC and you certainly know the specs. I ask because it’s hard for my to imagine a company like Groco offering a product that off the shelf doesn’t comply with ABYC ? Something doesn’t figure either the spec was written after the fact or ?

I recall working in ship and yacht yards lapping WC and Perko seacocks and servicing gate and globe valves. First time I ran into a Groco rubber plug seacock was bit shocking. However over the years I can’t recall a single one failing. As far as handle access, as you know that is an ongoing problem with sea valves and yachts period. I think sometimes the builder installs them under the rule—if you can see it then it’s okay.

Regards
Rick
 
I was asked aboard a Cruisers 45 ish boat by the owner. He was trying to figure out where his seacocks were. We traced the hoses and found them all finally. However the seacock for the generator was in sight but neither of us could even touch it. Talk about good design…
 
Lap is not the correct term However I found that removing, cleaning, and sanding my 40 year old rubber Groco plugs worked fine. Reinstall with silicone grease. Certainly a better option than the expense of replacing seacocks for a slight improvement in functionality. Are the newer Groco seacocks an improvement? Absolutely. In my opinion not worth the expense unless absolutely necessary.

I don't disagree, if these valves are sound, no reason to change them (except the integral valve/strainer).
 
Steve I’m not sure I recall ever running into Groco’s strainer valve units like this. I must have seen them but don’t recall. I am curious though about load ratings per ABYC and you certainly know the specs. I ask because it’s hard for my to imagine a company like Groco offering a product that off the shelf doesn’t comply with ABYC ? Something doesn’t figure either the spec was written after the fact or ?

I recall working in ship and yacht yards lapping WC and Perko seacocks and servicing gate and globe valves. First time I ran into a Groco rubber plug seacock was bit shocking. However over the years I can’t recall a single one failing. As far as handle access, as you know that is an ongoing problem with sea valves and yachts period. I think sometimes the builder installs them under the rule—if you can see it then it’s okay.

Regards
Rick

It would be a good question for Groco; I can't explain why they would offer a product like this, other than it seemed like a good idea at the time, eliminating a section of ostensibly "weaker" hose, and in a time where ABYC Standards were not well known. It is no longer offered, maybe that tells you all you need to know. And, I'm a fan of Groco products.

By the same token, if you hard plumb any fittings directly to a seacock, you potentially create the same issue, the part that protrudes furthest into the boat is where the 500 lbs. must be applied, the longer the appendage, the greater the leverage, the greater the likelihood of failure.
 
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