Winterising

Dec 2, 1997
8,842
- - LIttle Rock
That might depend on the shape of the tank. I don’t have a bypass so I just let my water heater fill with AF. I use an air compressor to blow that out, and in the spring I use your commissioning bleach solution to purge everything. By the time I get the bleach smell out there’s no AF smell or taste left.
Why not just use air compressor to blow all the water out of it instead of using antifreeze?
And fwiw, use the air compressor to blow all the water out of your fresh water plumbing? Because that would require disconnecting some the piping, replacing 'em with quick release fittings will make that a whole lot easier next year.

--Peggie
 
May 17, 2004
5,398
Beneteau Oceanis 37 Havre de Grace
Why not just use air compressor to blow all the water out of it instead of using antifreeze?
And fwiw, use the air compressor to blow all the water out of your fresh water plumbing? Because that would require disconnecting some the piping, replacing 'em with quick release fittings will make that a whole lot easier next year.

--Peggie
If I blow the tank dry first I don’t have a way to keep AF from running into the tank once I turn the pump on. That could be solved with a valve on the tank intake or a bypass loop, but since getting the AF out of the tank was never a big problem for me I just never bothered looking for the right adapters for my French designed metric plumbed tank and hoses. As AF gets more expensive it might become worthwhile. I’m certainly not suggesting my way is better than bypassing, just saying that for me getting the AF out is not a big deal.

I don’t trust that if I blow compressed air through all the hoses there won’t still be water sitting in a low spot. I’ve got two sinks, a freshwater fed head and a cockpit shower so I’m more comfortable knowing I’ve run AF through all of it.
 
Sep 25, 2008
7,239
Alden 50 Sarasota, Florida
If I blow the tank dry first I don’t have a way to keep AF from running into the tank once I turn the pump on. That could be solved with a valve on the tank intake or a bypass loop, but since getting the AF out of the tank was never a big problem for me I just never bothered looking for the right adapters for my French designed metric plumbed tank and hoses. As AF gets more expensive it might become worthwhile. I’m certainly not suggesting my way is better than bypassing, just saying that for me getting the AF out is not a big deal.

I don’t trust that if I blow compressed air through all the hoses there won’t still be water sitting in a low spot. I’ve got two sinks, a freshwater fed head and a cockpit shower so I’m more comfortable knowing I’ve run AF through all of it.
Keep in mind the fact that a trivial amount of water left will have enough room to expand when it freezes so as to not cause any damage. Only in confined spaces can it be problematic
 
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Jan 22, 2008
79
Hunter 30_88-94 Ipswich, Ma MA
That might depend on the shape of the tank. I don’t have a bypass so I just let my water heater fill with AF. I use an air compressor to blow that out, and in the spring I use your commissioning bleach solution to purge everything. By the time I get the bleach smell out there’s no AF smell or taste left.
We do the bleach “shock” treatment in the Spring prior to refilling the tank also. It really works keeping the water fresh and eliminating the rotten egg smell in the hot water.
 
May 17, 2004
5,398
Beneteau Oceanis 37 Havre de Grace
While I don't know when it actually gets solid, it is below the -50. Damage only occurs when the liquid becomes completely solid and further expansion then begins to break things.
One note on that - The -50 rating is the temperature where the AF freezes solid enough to burst metal. It may expand enough to burst plastic at a (maybe significantly) higher temperature. Citation - Engine Winter Freeze Protection - Marine How To
 

dLj

.
Mar 23, 2017
3,731
Belliure 41 Back in the Chesapeake
One note on that - The -50 rating is the temperature where the AF freezes solid enough to burst metal. It may expand enough to burst plastic at a (maybe significantly) higher temperature. Citation - Engine Winter Freeze Protection - Marine How To
That's good to know - I was under the impression that the freeze temperature was when the antifreeze began freezing - which gives a slushy range making the point of turning to solid a lower temperature - I can't find where I'd heard that so I'm going with you on this. For sure, when winterizing, make sure you get correct dilution anti-freeze in the system. Areas of inadequate dilution can break things.

It's funny, I was just looking earlier today at where I could get a freezer to test freeze points and freezing ranges. It's much more difficult to find a capable freezer than I'd anticipated. But I just read a short blurb in my local newspaper about how the local authorities did not do proper calibration of test equipment - giving rise to potential products not meeting their labeled ratings - I was thinking to find a freezer where I could check my local antifreeze supplier...

dj
 
May 17, 2004
5,398
Beneteau Oceanis 37 Havre de Grace
A refractometer is a pretty good way to check freeze point. I got one for like $20. It’s a good way to get some confidence that you don’t still have over diluted contents in the plumbing.
 
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dLj

.
Mar 23, 2017
3,731
Belliure 41 Back in the Chesapeake
A refractometer is a pretty good way to check freeze point. I got one for like $20. It’s a good way to get some confidence that you don’t still have over diluted contents in the plumbing.
those are great, but I'd really like to research the "slushy" zone.... But with the prices I saw on freezers with that capability - not going to happen unless I can find a freezer within my price range. Or I might look around and see if someone I know has a freezer with that capability and is willing to let me use it for ... pennies.... LOL

dj
 
Dec 2, 1997
8,842
- - LIttle Rock
I don’t trust that if I blow compressed air through all the hoses there won’t still be water sitting in a low spot. I’ve got two sinks, a freshwater fed head and a cockpit shower...
...You prevent that by disconnecting connections in the fresh water plumbing where that's likely to be a problem. You'd replace those connections with quick connect fittings as part of your spring recommissioning.

--Peggie
 

degas

.
Aug 14, 2023
10
Tanzer 29 Lake Ontario
I sail a Tanzer 29 on Lake Ontario.

My winterizing routine:

- Before haulout: Take down the sails & fold them. Change engine & transmission oil, fill fuel tank & add stabilizer, (every other year) replace fuel filters. (Yeah, I'll be running the engine after haulout to flush with antifreeze, but that's only for 5-10 minutes.) Pump out holding tank including flushing a couple of times with clean water. Empty the water tank.
- After haulout: Warm the engine then flush raw water system with 2 jugs of engine-friendly plumbing antifreeze. Seal the engine air filter & fuel tank vent & exhaust. Pour 1.5 jugs of regular plumbing antifreeze into the water tank & run it through the head & galley sinks. Pour 0.5 jug into head & pump into holding tank.
- Disconnect and bring the batteries home.
 
Dec 2, 1997
8,842
- - LIttle Rock
There's a better way to clean out the holding tank than just flushing clean water into it from the toilet: After last pumpout, put 4-6" of water into the tank via the deck pumpout fitting, 'cuz that sends it into the tank at the bottom to stir up any sludge and hold it in suspension so it can be pumped out. Pump that out, then repeat until you're pumping out clean water. If you have an overboard discharge pump, run clean water through the pump and its plumbing too.
It's a good idea to do this at least a couple of times during the season too.

--Peggie
 
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Sep 20, 2006
2,948
Hunter 33 Georgian Bay, Ontario, Canada
Hi Greg , do you use the pink plumbing A/F for the fresh water cooling portion of your engine? I see R/v pink plumbing for sale vs. the starbrite -50/-100 on sale at the marina store? I was planning the r;v pink for plumbing and the starbrite for the engine. Jabsco toilet manual says drain the toilet with the drain plug at base after pumping dry and thats it. H290 manual just says place A/f in bowl and pump into tank. Makes more sense to disconnect pick up line at thru hull and place in A/f jug as you say and pump thru system....conflicting info and want to be careful.
thanks again
Colin
Yes, the RV stuff is fine for plumbing, but always use Starbrite or other AF rated for engine use or you'll cause rust in the engine. I run a good 4 gals through mine ( 17 yrs. Georgian Bay ) may be a little overkill, but I have seen the results ( not mine ) of not getting enough AF into the engine and leaving a mix of water and AF. AF is cheap compared to a new engine.

I also take a pancake compressor and blow out all the lines to the taps rather than deal with AF taste in the spring.
 
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Jun 9, 2008
1,780
- -- -Bayfield
For the inboard, you want to make sure you use a non-toxic engine antifreeze so protect the environment I know lots of boaters go for the pink stuff that is offered at a very inexpensive price (and even reads on the label that it is good for engines), but it is not good for internal engine parts like a good antifreeze product. You get what you pay for. So, a simple way to winterize your inboard is to run antifreeze into the fresh water intake hose, or filter, or whatever makes sense and is easiest. If you have an engine strainer, this is a good time to clean it. Also remember to close the sea cock so you put the antifreeze in the engine and not on the ground or in the water. Have someone watch at the exhaust where it comes out of the boat and when it is evident that you can see good color of the antifreeze, then you can feel confident that you have done a good job. But, to just arbitrarily say I just put one gallon in and then not know if you are really putting enough in, is crazy. First of all, you will be pushing water out of the engine first and then the antifreeze takes over. If you really want to be certain, after running the antifreeze through, you can open any engine block pitcocks to drain any raw water out of the block (not the closed system, if you have one, but the raw water side). Also larger engines might have water coolers that could be drained. If you have an owner's manual, it is a good thing to make sure you have all your bases covered. If you have a hot water heater and heat exchanger, that will require more antifreeze. And you will have an aqua lift muffler that might have a drain plug you can open to drain water out of it. If no drain plug, you should be OK if you ran enough antifreeze through the engine and out of the tail pipe.
If you have a genset (generator), then you'd do the same.
Also, changing the oil is usually a good practice in the fall too. And, it is easier to extract warm oil than cold oil.
For fresh water systems, I always just open up the faucets and let the demand pump run until the water starts spurting out the faucets. Then I run the pink stuff from the water tank out each faucet or shower head until you get a good solid pink color. If it is good for -50 or more, you should be good to go.
For the head, the first thing you need to do is pump out the holding tank. You don't want a full or half tank freezing and busting open inside the boat due to freeze expansion. You'll have a nasty clean up job come spring. After pumping, I then pour the pink stuff into the tank and pump the head until some pink comes out in the toilet bowl. That way you know you have antifreeze in the pump too. You can pour some into the bowl and pump, but that doesn't cover the side from the tank.
For reverse cycle AC/heat I have an intake strainer near the intake cockpit and I pour antifreeze into that and turn on the unit. After a bit you should see the pink stuff coming out of the exit fittings.
I also put antifreeze in the bilge and make sure the bilge pumps operate to run antifreeze through them.
i guess that is about it. I hope I didn't forget anything.
 
Dec 2, 1997
8,842
- - LIttle Rock
Not quite how I recommend winterizing the sanitation system (toilet and holding tank.)
If you go to the Plumbing and Sanitation forum, you'll find an article at the top of it (a "sticky") ''Winterizing Plumbing'' that includes instructions for winterizing both fresh water and sanitation systems. If you don't want to go there, this is the correct way to winterize the sanitation system:
SANITATION SYSTEM
The sanitation system is the easy job:

Pump out the holding tank, then rinse thoroughly to flush out any sludge. This does not require filling the tank and can even be done with sea water. Here’s how:
Put enough water into the tank via the deck pumpout fitting—because that sends the water into the tank at the bottom to stir up any sludge and hold it in suspension so it can be flushed out-- to cover the bottom to a depth of at least four inches. Pump that out. Repeat…repeat…repeat…till you’re pumping out clean water. Then add water one more time and turn on the macerator to rinse it out along with the overboard discharge plumbing.
Alternatively, you can use a washdown pump to do the whole job. Stick the nozzle into the deck pumpout out fitting and turn on the water. When the depth reaches a few inches, leave the water running and turn on the macerator pump. Let both run till the water runs clean (it may be best to do this offshore outside the “3 mile limit”).
By the way, this should be done at least 2-3x a season, more often if live aboard or use your boat year round and in preparation for any extended layup, not just winter layup
000000000000
Now you’re ready to winterize the system.
Sea water toilet, manual or electric: Just flushing antifreeze through the bowl will not protect the intake line, the toilet pump or the bowl...it'll only go out the discharge to the tank. To protect the whole system, it's necessary to close the toilet intake through-hull, disconnect inlet hose and stick it in a gallon of non-toxic ("the pink stuff") antifreeze. Pump the whole gallon through the system into the holding tank. Do not reconnect head intake hose to the through-hull.
If your toilet’s flush water intake line is teed into the head sink drain line, you can add the antifreeze by just pouring it down the sink--after you've closed the drain seacock, of course! Pump the head or hold the button down long enough to get as much of the excess fluid out of the system as possible.
Fresh water toilet: If your toilet uses onboard pressurized fresh water, you winterized it when you winterized your fresh water system. All that remains is, flush the appropriate amount of non-toxic antifreeze ("the pink stuff") down the toilet into the tank.

Do not use antifreeze in an ElectroScan, Lectra/San, PuraSan, or any other Type I or Type II MSD. Follow manufacturers instructions to winterize all Type I and II MSDs.

After the boat comes out of the water, open all the sea cocks to drain any trapped water. (Omit this step if the boat will remain in the water).

And you’re done!

--Peggie
 
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Jun 8, 2004
1,042
C&C Frigate 36 St. Margarets Bay, Nova Scotia
My diesel is winterized at the time of haul out. After I motor over to travelift slip, I leave the engine idling, close the cooling water intake seacock, open the top of the seawater strainer, and pour in full strength ethylene glycol (not the pre-mixed), monitoring the exhaust for a strong indication (colour) of glycol in the discharge water. As noted above, ethylene glycol has low toxicity for marine organisms. Once the glycol has flowed through the raw water pump, heat exchanger and water lift muffler (usually about 1/2 a gallon for my Yanmar 3GM30) I shut down the engine. I then do an oil change while the oil is hot, usually immediately after haul out. As for the potable water system, I can't stand the taste or smell of any of the "pink' RV antifreeze stuff. I drain it and blow everything clear, using a shopvac with a step-down adaptor. The Jabsco head gets drained as per the manufacturer's recommendation. I vigorously pump the handle in both valve positions to make sure no water is left in the pump. I have used this method for over 30 Canadian winter without any issues.
 
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Sep 26, 2008
634
Hunter 340 0 Wickford, RI
Keep in mind the fact that a trivial amount of water left will have enough room to expand when it freezes so as to not cause any damage. Only in confined spaces can it be problematic
Don is so right. Confined spaces are the issue.
This is what a trivial amount of water can do. Picture is worth a thousand words.
 

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Oct 6, 2007
1,071
Hunter H30 1982 Chicago IL
I may be a bit late to this thread, but here is my process for winter storage in Chicago:

Water Heater - RV by-pass kit installed. No antifreeze. Just drain it. Opening the pressure release valve helps it drain faster.
Waste tank - pump out and triple rinse.
Head - Pump ½ gallon of -70°F antifreeze through the head. Don’t just dump it in the bowl. I use the antifreeze for engines here, not the pink stuff, because I think the lubricant and corrosion inhibitors are probably good for the pump.
Water system - Non-toxic pink -50°F antifreeze. Pumped through cold, then hot faucets one at a time at each sink each sink until pure undiluted antifreeze is running out . Start with sinks closest to the pump, progress to further away. My 30’ boat takes about three gallons. No antifreeze in the water tank. I drain it and leave the inspection ports open.
Engine (Yanmar 2GM raw water cooled) - Drain and clean sea strainer. With engine hot so antifreeze does not by-pass the engine block, run through 1 gallon of -70°F first and then 2 gallons of -100°F antifreeze. Two gallons total might be enough for my little engine but the third is cheap insurance.
Bilge - Drain, then add ½ gallon of the ‘70°F plus whatever remains in the bottom of the other antifreeze jugs. Part of this goes into the bilge via the ice box drain. This protects the ice box drain hose and the primary bilge pump in case significant condensation or rain collects the bilge.
Cabin - Place 8 DampRid buckets around the cabin to prevent condensation.

Steamlined process - For the engine, head and water system, I used to loosen clamps, pull to hoses off and attach an extension hose to stick directly into my jugs of antifreeze. No buckets or funnels but it was always cumbersome, messy and time consuming. I’ve since streamlined the process by installing 3-way valves and permanent winterizing hoses at each which I also just stick directly into the antifreeze jugs. The 3-way valves are located just above the head intake seacock, at the water tank outlet and just after the engine raw water sea strainer. The engine winterzing hose extends into the bilge where it could double as an emergency bilge pump. The water and head winterizing hoses just coil up and lay in their respective lockers. Open the engine and head seacocks to drain after haul out.
 
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jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
21,998
CAL 35 Cruiser #21 moored EVERETT WA
You would make a great Procurement Officer. :beer: