How cold does it have to get to break a seacock?

[Skipper]

I'm an experience sailor\boater....from California. This winterizing thing is not on my list of mastered tasks, even though I've done it 3 times now.

The drain holes in seacocks don't get enough boat media attention in my view. It took me some time to ascertain that there even were drain holes at all. The thought occurred to me when I read on Boat US that to properly winterize a sink-drain seacock, you merely pour AF into the sink and then close the seacock. I'm guessing that this action will put AF in the seacock, and trap it in the barrel when it's closed.

The problem is seacocks that you can't do this with, like the raw side engine intake or the head intake, where I've stuck the removed intake hose into AF and sucked it up into the heat exchanger and out the stern, or into the head. There's still water in the close seacock barrel.

So I found the drain holes. But the head intake seacock's drain screw won't budge. All the seacocks are bonded (except the engine intake), so there might be some corrosion in the screw, even though the seacock look good with only minor greenery.

Have these things busted before because of this? How cold does it have to get to break a Wilcox Crittenden bronze seacock? What happens if it breaks in this way?

 

[Maine Sail]

I'm an experience sailor\boater....from California. This winterizing thing is not on my list of mastered tasks, even though I've done it 3 times now.

The drain holes in seacocks don't get enough boat media attention in my view. It took me some time to ascertain that there even were drain holes at all. The thought occurred to me when I read on Boat US that to properly winterize a sink-drain seacock, you merely pour AF into the sink and then close the seacock. I'm guessing that this action will put AF in the seacock, and trap it in the barrel when it's closed.

The problem is seacocks that you can't do this with, like the raw side engine intake or the head intake, where I've stuck the removed intake hose into AF and sucked it up into the heat exchanger and out the stern, or into the head. There's still water in the close seacock barrel.

So I found the drain holes. But the head intake seacock's drain screw won't budge. All the seacocks are bonded (except the engine intake), so there might be some corrosion in the screw, even though the seacock look good with only minor greenery.

Have these things busted before because of this? How cold does it have to get to break a Wilcox Crittenden bronze seacock? What happens if it breaks in this way?

If those drain screws have not been removed before I would not attempt this, in the water. If it gets real cold simply stick a 150W light bulb next to the seacock. Stored in-water in the Chess you are not very likely to split a seacock as the sea water will likely not ever get below 32F....

In Maine this can be a different story..

 

[Don S/V ILLusion]

It's not always wise to keep power on the heaters or lights in the winter while unattended and many marinas also warn against such tactics for obvious reasons, not the least of which is the inevitable power outage.

If the boat is in wet storage, it's usually best to simply remove the hose(s) so any trapped water can expand up rather than outward breaking the seacocks. A properly functioning and maintained seacock should not leak appreciably without hose attached.

 

[Skipper]

If those drain screws have not been removed before I would not attempt this, in the water. If it gets real cold simply stick a 150W light bulb next to the seacock. Stored in-water in the Chess you are not very likely to split a seacock as the sea water will likely not ever get below 32F....

In Maine this can be a different story..

Thank you, Mainesail. So how cold did it have to get to break that one?

 

[Maine Sail]

It's not always wise to keep power on the heaters or lights in the winter while unattended and many marinas also warn against such tactics for obvious reasons, not the least of which is the inevitable power outage.

If the boat is in wet storage, it's usually best to simply remove the hose(s) so any trapped water can expand up rather than outward breaking the seacocks. A properly functioning and maintained seacock should not leak appreciably without hose attached.

Don,

We are talking about the water that is trapped in the ball or cone when rotated 90 degrees. This water has nowhere to expand but to split the valve or cone. Valve manufacturers install drain plugs so that you can physically drain the ball or cone to prevent freezing.. The two in the photos above were not properly drained..

 

[Maine Sail]

Thank you, Mainesail. So how cold did it have to get to break that one?

Got me???? Those were found in the spring. All I can say is that both of those winters had peak lows of about -6F and -13F...

 

[Charles Erwin]

Apparently fresh water begins to expand at about 4 degrees C and continues until it is frozen at about 0 C or 32 F. Seawater is frozen at slightly lower temperature - about 28 F. Full expansion is about 9%

So if it is cold enough to freeze water in the bilge then it is probably cold enough to freeze the water trapped in the valve body and break the casting.

Charles

 

[shemandr]

If the seacocks were left open rather than closed, the water would not be trapped inside - right?
So what is the recommendation with regard to open or closed for boats stored on the hard, outside or inside?

 

[JustDucky]

open

 

[Rich Stidger]

Recommendation? Maybe, but in any event here is what I do:

Storage on the hard- I generally winterize all my system while I am in the water at the dock and I leave the seacocks closed until after hauling. Then I open the seacocks and let them drain, and then close them for the winter.

In the water storage- I winterize as usual and then using a drill-powered pump, I pump antifreeze backwards into the seacock and out into the water. While pumping, I close the seacock trapping antifreeze in the center of the ball. I use regular automotive antifreeze that will actually protect to -30 F, not the pink stuff that turns to slush at a much higher temperature. I do use the PG vs the EG formulation when I can get it.

 

[Cwoody]

For winterizing the engine raw water intake while in the water, here is what I do. Once I have run AF through the engine and shut off engine.

1. Close engine raw water seacock off.
2. Fill engine raw water strainer with AF.
3. Open raw water seacock
4. Gravity will drain AF in strainer out of seacock.
5. repeat 2 and 3
6. Close off raw water seacock.

I actually use the strainer to get AF into the engine as well.
1. Close Engine raw water seacock.
2. Open strainer and fill w/ AF
3. Start engine and continue pouring AF into strainer. (1 gal)
4. Shut off engine

 

[Maine Sail]

For winterizing the engine raw water intake while in the water, here is what I do. Once I have run AF through the engine and shut off engine.

1. Close engine raw water seacock off.
2. Fill engine raw water strainer with AF.
3. Open raw water seacock
4. Gravity will drain AF in strainer out of seacock.
5. repeat 2 and 3
6. Close off raw water seacock.

I actually use the strainer to get AF into the engine as well.
1. Close Engine raw water seacock.
2. Open strainer and fill w/ AF
3. Start engine and continue pouring AF into strainer. (1 gal)
4. Shut off engine

Here in Maine even sucking in 2 gallons can and does split heat exchangers. People very, very often suck in far too little AF.

This owner from the pic below thought it a reasonable approach to save $6.00 on propylene glycol antifreeze. He decided to suck just two gallons of -50 PG into his expensive engine. Once he "saw pink" out the exhaust he immediately shut the engine off.

Merely "seeing pink" arrive at the aft end means very little unless you previously know exactly how much it takes.. If in doubt it is best to measure the concentration coming out the exhaust by catching it in a cup and then measuring it with a sight refractometer. Alternatively spend the extra $$ & suck in a couple more gallons of PG. The concentration coming out the wet exhaust should ideally match very closely as to what it went in at.

This owner froze and split his expensive heat exchanger. It cost a lot more than the $6.00 he saved on antifreeze.

This is what remained inside the HX in the spring. Please understand that when you suck in a gallon of antifreeze it does not simply displace 1 gallon of water. IT MIXES with the water already in the system. Pre-diluted propylene glycol, as in -50 etc., should not get diluted any further...

You may get away with saving a penny in the mid Atlantic region but in the far North you can run into serious trouble.

Seeing as it is next to impossible to photograph my sight refractometer, what is used to measure PG concentrations, I used a test strip specifically designed for PG..

As a point of reference this was two gallons sucked through a Universal M-25 diesel engine. I measured the freeze point of what was in the heat exchanger at just 25F!!!!!

 

[Gunni]

Any attempt to get AF into a thru-hull in wet storage assumes that it will not leak out or be replaced by seawater because this ancient thing isn't water tight either. In the middle-bay that water will be brackish, and freeze at a higher temp.

While Mainsail is right and it is less of a risk in our milder climate, and plenty of boats survive unscathed in the water around here, we are one hard winter away of heartache. If I had a faulty thru- hull like this I would incur the cost of a short haul (at the least) to get the drain fixed, or replaced. Better yet haul her for the winter and make it a leisurely winter project.

 

[Ken Cross]

Where we live (Everett, Wa marina) the whole marina is now frozen (brackish water). I open all interior cabinets and engine compartment. I heat to about 50 to 55 degrees f with a small electric fan running to distribute the air. So far it seems to work, but for us frozen water in the marina is usually only a couple of weeks per year. I do check on her once in a while. In case of power failure I should put the diesel furnace on set cooler than the electric cabin heater so in event of power loss the diesel heat could take over until the battery is exhausted. I haven't tried that yet. To my knowledge so far we have never lost power in our slip.

 

[Skipper]

For winterizing the engine raw water intake while in the water, here is what I do. Once I have run AF through the engine and shut off engine.

1. Close engine raw water seacock off.
2. Fill engine raw water strainer with AF.
3. Open raw water seacock
4. Gravity will drain AF in strainer out of seacock.
5. repeat 2 and 3
6. Close off raw water seacock.

I actually use the strainer to get AF into the engine as well.
1. Close Engine raw water seacock.
2. Open strainer and fill w/ AF
3. Start engine and continue pouring AF into strainer. (1 gal)
4. Shut off engine

This post made me think of a possible remedy for my issue: I can use a separate spare hose, and clamp it to the head intake seacock - fill the hose with AF in the vertical position, and feed the AF to the seacock, then close the seacock, and even leave the hose attached with the other end tied up above the waterline, still with AF in it - so that if there is actually seepage past the thru-hull, it will seep AF down and I can check it to confirm.

I can't use the head intake's hose for this, as it is routed through the cabinetry in such a way as to make it a bear to do so. But a spare loose hose would work.

 

[Skipper]

Here in Maine even sucking in 2 gallons can and does split heat exchangers. People very, very often suck in far too little AF.

This owner from the pic below thought it a reasonable approach to save $6.00 on propylene glycol antifreeze. He decided to suck just two gallons of -50 PG into his expensive engine. Once he "saw pink" out the exhaust he immediately shut the engine off.

I use the blue stuff (-100) on the raw side of the engine. The mix even at 1 to 1 is still rated at like -20, which is drastically better than the pink when mixed. That's why I use it on the engine, because you never know where water might be hiding in there.

 

[wflowe2]

We have a "bubbler" system on the docks that pumps warmer water from deeper in the lake up too the surface. this keeps ice from forming around he hull. I'm assuming that since there isn't ice around the boat, thru hulls below the water line should be OK.

 

[Ron20324]

...so that if there is actually seepage past the thru-hull, it will seep AF down and I can check it to confirm. I can't use the head intake's hose for this, as it is routed through the cabinetry....

I went deluxe, and tee'd the head intake off the sink drain. Put AF in the sink, opened/closed the thruhull quickly to flood with AF, then pump to and through the head. All is treated.

 

[Skipper]

This post made me think of a possible remedy for my issue: I can use a separate spare hose, and clamp it to the head intake seacock - fill the hose with AF in the vertical position, and feed the AF to the seacock, then close the seacock, and even leave the hose attached with the other end tied up above the waterline, still with AF in it - so that if there is actually seepage past the thru-hull, it will seep AF down and I can check it to confirm.

I can't use the head intake's hose for this, as it is routed through the cabinetry in such a way as to make it a bear to do so. But a spare loose hose would work.

Done. Dang that was easy. Removed working hose, clamped spare loose hose, filled hose with AF, opened seacock, closed seacock, removed spare hose, replaced working hose. Got all worked up for nothing.