Seacock Quality... Replace?—Currently on the hard.

[testingthewaters91]

There is some risk management balance there. Exhaust hose is much more robust than most other drain and intake hoses, so there is less likelihood of failure there. Also if you ever forgot to open an exhaust seacock before starting the engine it would make for a pretty bad day, worse than if you forgot to open any other seacock. I think (though I haven’t read the spec myself) that ABYC exempts exhausts from the seacock requirement for these reasons.

Oh my. That's a scary thought. It would certainly make for a bad day.

Thanks for all the feedback so far.

I’m going to go ahead and replace the two hoses in the aft compartment with robust marine-grade hose and double clamps set 180 degrees apart. That should hold up solid for the next couple years until the next haul-out.

For the seacocks, I’m planning to swap in brass (edit: I meant to say bronze) for four total: the galley sink, engine intake, marine head sink, and what I think is waste discharge. I believe the engine intake is half inch, the galley sink and waste discharge are inch and a half, and the head sink might be three-quarter or maybe even half inch—I’ll double check, but if anyone knows the correct sizes on a Hunter 30, I’d appreciate the confirmation.

A few of these had no valve at all, including the marine head sink discharge, which surprised me. I’ve attached a few more photos including the engine intake.

Appreciate all the help and opinions so far—grateful to learn from the community.

 

[Davidasailor26]

I’m planning to swap in brass for four total

Swap in bronze, not brass. Brass is susceptible to dezincification, leaving it pink and brittle.

 

[kappykaplan]

Swap in bronze, not brass. Brass is susceptible to dezincification, leaving it pink and brittle.

 

[testingthewaters91]

Swap in bronze, not brass. Brass is susceptible to dezincification, leaving it pink and brittle.

Ahhh! I keep mixing them up—I meant bronze! Shows you how much of my brain is left after all this.

Also, I’ve verified the aft thru hulls are above the waterline, thankfully!

You can see in the attached picture.

Still wondering if my thru hulls are brass or bronze, or if it's just the fittings.

 

[dLj]

Just a note - the double hose clamps is not required by ABYC. It is commonly stated as needed but that is not correct. The danger of using double hose clamps is often the nipple is not long enough to fully accommodate both hose clamps without one of the hose clamps clamping down right at or slightly over the end of the nipple. That actually causes a stress riser on the inside of the hose that makes it less reliable than one hose clamp.

If your nipple where you are clamping is long enough where that doesn't happen, then it's fine to use two. But it actually doesn't give added security.

What you do need to use are hose clamps that are solid. Not the kind with threads open which are the more common ones found.

Ones like these:

316 Stainless Steel Hose Clamps

316 Stainless Steel Hose Clamps Solid Band All 316 Stainless Steel

www.fisheriessupply.com

dj

 

[testingthewaters91]

T

Just a note - the double hose clamps is not required by ABYC. It is commonly stated as needed but that is not correct. The danger of using double hose clamps is often the nipple is not long enough to fully accommodate both hose clamps without one of the hose clamps clamping down right at or slightly over the end of the nipple. That actually causes a stress riser on the inside of the hose that makes it less reliable than one hose clamp.

If your nipple where you are clamping is long enough where that doesn't happen, then it's fine to use two. But it actually doesn't give added security.

What you do need to use are hose clamps that are solid. Not the kind with threads open which are the more common ones found.

Ones like these:

316 Stainless Steel Hose Clamps

316 Stainless Steel Hose Clamps Solid Band All 316 Stainless Steel

www.fisheriessupply.com

dj

Thank you. Will keep that in mind.


I'm thinking of keeping this fuel intake Seacock as is, because I believe it may be bronze (and it opens and closes like it should unlike the others). It looks so different to the others I posted. Right?

 

[testingthewaters91]

And I found one more! Thankfully this one also looks brass and has a backing plate.

 

[Tally Ho]

My Hunter 280 had an engine exhaust that exited below the water line. It did not have a valve. As has been stated, exhaust hose is pretty robust, but be sure to inspect it and also the hose clamps annually.

My current boat (O’Day 322) has cockpit scupper drains and propane locker drains that are “technically” above the water line, as well as a head sink drain. But all of these would be under water when sailing (depending on which tack I am on).

None of these have valves, but I did replace all of the old nylon thruhulls (some were cracked).



Greg

 

[testingthewaters91]

My Hunter 280 had an engine exhaust that exited below the water line. It did not have a valve. As has been stated, exhaust hose is pretty robust, but be sure to inspect it and also the hose clamps annually.

My current boat (O’Day 322) has cockpit scupper drains and propane locker drains that are “technically” above the water line, as well as a head sink drain. But all of these would be under water when sailing (depending on which tack I am on).

None of these have valves, but I did replace all of the old nylon thruhulls (some were cracked).

View attachment 232457 View attachment 232459 View attachment 232458 View attachment 232456

Greg

These sit just above the waterline while in the marina. You can see it in the pre-wash photo I’ve attached—right in front of the rudder, just above the grime line. Not by much, but they’re above.

 

[jssailem]

And I found one more!

This is feeling like an Easter egg hunt.

Walk about the bottom of the boat and identify all the holes in the hull.
For example:

1. Water Intake Galley 0.5" Diameter
2. Water Drain Galley 1" diameter

Once you have found all the holes, you go inside and match the holes with the through-hull components.

1. Water Intake Galley "Old Brass 0.5 " Ball Valve, 0.25" reduction nipple, 0.25" hose, 3ft long to sink raw water pump". REPLACE ALL

Now that you know what is going on with each of the systems, you can create a list of parts that you need and eliminate the ones that you decide are okay.

The Exhaust hose is part of an "Engine Exhaust System." You do not want a valve in that system. If you or one of your crew starts the engine without having opened the valve, the engine will malfunction. Please take the time to understand the system.
Here are three typical designs for engine exhaust systems. Note the level of the water line in these systems. Your boat may be different. If it is, it needs a system to address its own design (i.e., the engine sits below the waterline).

Here is an example of a flawed design and the alterations needed to fix the issues. The level of the water line is a critical factor in the design of the engine exhaust system.

Based on your images, the exhaust port will be just above the water line when the boat sits in calm water. When sailing, the water line will change, and the exhaust port will sometimes be below it. Your internal exhaust hose design must address that issue to prevent a siphon risk.

You stated you are considering replacing the exhaust hose. Double clamps should be used on the exhaust hose. Do not change how the exhaust hose is routed through the boat without carefully considering the design and how it will be affected while the boat is moving in the water.

 

[testingthewaters91]

This is feeling like an Easter egg hunt.

Walk about the bottom of the boat and identify all the holes in the hull.
For example:

1. Water Intake Galley 0.5" Diameter
2. Water Drain Galley 1" diameter

Once you have found all the holes, you go inside and match the holes with the through-hull components.

1. Water Intake Galley "Old Brass 0.5 " Ball Valve, 0.25" reduction nipple, 0.25" hose, 3ft long to sink raw water pump". REPLACE ALL

Now that you know what is going on with each of the systems, you can create a list of parts that you need and eliminate the ones that you decide are okay.

The Exhaust hose is part of an "Engine Exhaust System." You do not want a valve in that system. If you or one of your crew starts the engine without having opened the valve, the engine will malfunction. Please take the time to understand the system.
Here are three typical designs for engine exhaust systems. Note the level of the water line in these systems. Your boat may be different. If it is, it needs a system to address its own design (i.e., the engine sits below the waterline).

View attachment 232460
View attachment 232461
View attachment 232462

Here is an example of a flawed design and the alterations needed to fix the issues. The level of the water line is a critical factor in the design of the engine exhaust system.
View attachment 232463

Based on your images, the exhaust port will be just above the water line when the boat sits in calm water. When sailing, the water line will change, and the exhaust port will sometimes be below it. Your internal exhaust hose design must address that issue to prevent a siphon risk.

You stated you are considering replacing the exhaust hose. Double clamps should be used on the exhaust hose. Do not change how the exhaust hose is routed through the boat without carefully considering the design and how it will be affected while the boat is moving in the water.

Thanks a ton for the detailed reply—it really does feel like an Easter egg hunt, and I’m learning fast. First boat, so I’m definitely soaking it all in.

I did a walkaround underneath and somehow still missed one. I’ll go back after work and recheck, but the boatyard mechanic is hoping to get the parts list today so he can order by the weekend.

As far as I can tell, I don’t have a seawater intake for the galley—just a freshwater tank under the starboard settee that feeds the system. No raw water intake there, so thankfully that’s one less seacock to worry about.

The exhaust setup matches your diagram almost exactly, and the siphon issue is definitely on my radar. That hose was replaced two years ago with the engine rebuild, so I may leave it alone for now and revisit in a couple years when I know the boat better.

From what I’ve ID’d so far:

The 90° one with the backing plate looks like decent brass—seems solid.

The engine intake looks like brass as well.

The two larger 1.5" valves seem like bad-quality bronze or maybe even brass—definitely on my list to replace.

The head sink discharge just go straight to hose below water line—no valve at all.

I’ll make sure everything gets double clamped where needed, marine-grade hose only, and keep things simple for now so the yard can wrap it up safely and I can move aboard.

Appreciate the help and the diagrams—it really helps clarify things. Let me know if I’m missing anything obvious.

 

[BigEasy]

As far as I can tell, I don’t have a seawater intake for the galley—just a freshwater tank under the starboard settee
The head sink discharge just go straight to hose below water line—no valve at all.

Usually there is no seawater intake for the galley sink, unless the PO added.
You should add a valve on the head sink discharge.
You haven't mentioned a sea water intake for the head. It's usually 3/4" or smaller; source for sea water to flush the toilet. It should
have an intake, valve, & hose near the toilet or under a cabinet in the head area.

 

[testingthewaters91]

I believe this is the marine head water intake. I think it's in good condition. No leaking and looks to be bronze.

 

[BigEasy]

After you identify & replace the fittings, might be a good idea to label them with plastic tags as well as drawing a schematic detailing the location of each fitting. That info was present in my owner's manual. Purchase conical wooden plugs for use in an emergency; some actually attach a plug to each thru hull to ensure that the plug is readily available.

 

[jssailem]

keep things simple for now so the yard can wrap it up safely and I can move aboard.

I understand the urgency.
Simple observations.

• Use BRONZE, not BRASS, valves with flanges and backing plates on boat through-hulls.
• Marine-rated hoses with double clamps are required when below the water surface.
• Ball Valves, not Gate Valves, are on boats' through-hull valves.
• Think systems, not individual components.

 

[kappykaplan]

Purchase conical wooden plugs for use in an emergency; some actually attach a plug to each thru hull to ensure that the plug is readily available.

 

[jssailem]

I believe this is the marine head water intake.

I understand the issue of belief, but I'm not sure yet.
It is your boat. You must KNOW!
That means you must get into places your crew, friends, or family will never go. You must trace the hoses and wires to know where they go and what they do.

I understand it is a new boat. Some things may not look correct. I suggest you take your time and validate what and why something is the way it is. No Rush.

Think about the healthy aspects of bending and contorting your body to find your boat's hidden spaces. It is known as Boat Yoga.

 

[testingthewaters91]

I understand the issue of belief, but I'm not sure yet.
It is your boat. You must KNOW!
That means you must get into places your crew, friends, or family will never go. You must trace the hoses and wires to know where they go and what they do.

I understand it is a new boat. Some things may not look correct. I suggest you take your time and validate what and why something is the way it is. No Rush.

Think about the healthy aspects of bending and contorting your body to find your boat's hidden spaces. It is known as Boat Yoga.

Boat yoga—haha, yeah, I’m quickly becoming a believer.

As for the flanges, I’m still on the fence. My 1981 Hunter has solid fiberglass hulls, not cored, so it might be a bit thinner than newer boats. I’m a little hesitant about through-bolting flange bases if I’m not confident in the thickness. It’s not off the table, but since the yard guy is on a tight schedule and wants to move things along, I’m leaning toward inline bronze seacocks for now, just to keep the job moving.

That leads to my next question—through-hulls. How tough is that replacement process, generally speaking? If I find the through-hulls are bronze, should I just keep them and only replace the brass valves? Or is it smarter to replace both, even if I’m pressed for time?

Really appreciate your perspective—trying to make the best call without dragging out the yard stay longer than necessary.

 

[testingthewaters91]

If you go through the trouble of taking them apart I would replace them. Your contractor is not offering the best advice, and recommending the wrong backing material. Don’t waste your time and money on half measures

I may leave them in the boat and just try to test their integrity. This boat yard does not want to do a lot of work on my boat.

How could I tell is this thru hull fitting is bronze or brass?

 

[TrapperJohn]

I'm in the process of replacing my first thru-hull. The summary, so far, is here.

The part of your posting that would worry me is this (I cut these pictures down a little in size):

Maybe there's a recessed head on the thru-hull or maybe you have something I ran into:

This was under the static water line so I was glad at least there was a valve there. Yours appear to be just above so that's up to you how you would handle it.

What concerns me is what I found. The flange base for mine was buried in the hull layup. The hull thickness at the flange is only about 3/8 inches versus about a 5/8 or 3/4 inch thick hull for the surrounding area. (Can't really tell because of the grinding I did to get the old one free.) What was worse, there was no thru-hull "head" (mushroom or recessed) there. Instead I found a plastic sleeve embedded in the hull. You can see it as a shadow in the first picture and it was visible once I sanded off the bottom paint. The 2nd picture shows what was left of the sleeve when I finally got it out. The rest was shavings all over the ground.

I'm not an old hand at this but I would be concerned if there wasn't even a bronze or Marelon thru-hull installed underneath those piles of fiberglass/epoxy. What I ended up with, after getting the plastic out, was a big hole 1/4" wider than the thru-hull fitting. A gap I'm going to have to fill in to get a proper seal.

Someone else mentioned the concern of the corrugated hose connected from the bilge pump. This is easily cut or broken off even when new. It may be above the waterline now but in choppy water or a big sea, they may not be.

Just some of my thoughts.

ETA: The rudder post appears to have a stuffing box so there must have been some concern by the builder of water ingress at a point higher than those other thru-hulls.