Winterization fluid

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paulga

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Joined
May 28, 2018
Messages
1,025
Location
United States
Vessel Name
DD
Vessel Make
Marine Trader Sundeck 40'
My boat has single screw Ford Lehman sp135 6 cylinder and a westerbeke 6 kw 6.0BCD Genny. I also plan to add some AF to the rear water tank. How much of this winterization fluid so I need?

I saw the west marine antifreeze is sold twice as expensive, so there should be a reason?
 
You should use the pink RV/marine antifreeze. $4-5.00 per gallon at WalMart.

Do not put antifreeze in your fresh water tank. It will take about 5 gallons to dilute the existing water to 50% and it will take lots of flushing to get the taste out in the spring.

Instead, disconnect the suction hose to the pump. Replace it with 2-3’ piece of hose that you put the open end in a jug of antifreeze. Then run a bypass hose (sometimes all you have to do is turn a few bypass valves if it has been set up already) around the water heater and drain it down. Otherwise it will take another 5 gal to get to 50% and you will also have to flush lots of water through to get the taste out.

Use the fresh water pump to suck it up from the jug and run it until each fixture, hot and cold, runs pink. Takes just a few gallons to do the whole boat this way.

Also dump a cup or two of antifreeze in each drain to fill the P trap.

David
 
My boat has single screw Ford Lehman sp135 6 cylinder and a westerbeke 6 kw 6.0BCD Genny. I also plan to add some AF to the rear water tank. How much of this winterization fluid so I need?

I saw the west marine antifreeze is sold twice as expensive, so there should be a reason?

I use the 3.99/gal Walmart stuff for my water system as it is a true RV/Marine antifreeze made to go in water system. It’s ok to use in the raw water side of an engine, but the 6.99 stuff at West Marine is different with added rust inhibitors, better for engine use on the raw water side. It is not a substitute for true engine anti freeze used in closed cooling systems.

As far as using the 3.99 stuff in your water tank…run your tank as empty as you can and then put a couple gallons in. That is all you need to flush out the water lines. Been doing it that way for many years
 
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how many gallons of fluids are needed for the engine and generator?
 
how many gallons of fluids are needed for the engine and generator?

I use about 5 gallons on our Sp135 / GB 36. Maybe 3 gallons for the generator. I can do the whole boat with about 15 gallons. (Single engine) If you have mufflers, look for a drain plug and drain the water from each muffler first. Leave the plug out. Stop feeding the engines antifreeze when it drains from the muffler good and pink. No need to spend $$$ on filling mufflers with antifreeze. Be sure to bypass hot water heater, drain water tanks, etc.
 
Personally I spend the extra few bucks on the West Marine stuff, as it contains propylene glycol only, and not alcohol like the cheap antifreeze usually does.

For my twin engine boat, we usually go through 34 - 36 gallons of antifreeze. That's for 2 engines (no muffler drain plugs on my boat, so each engine gets 9 gallons to get all the way through the system and avoid too much dilution), a generator, 3 A/C systems, 2 heads, an anchor washdown, and the fresh water system.

If you have muffler drains, that'll reduce the amount of antifreeze needed for the engines as mentioned previously. Definitely bypass and drain the water heater.
 
Paul appears to be a new boater, or just new to trawler size boat and is exercising extreme caution. Kudos.

The following is for boats left in the water year round.
My boat(s) do not get winterized unless you count the airvents to engine room are covered leaving standing air (uncirculated) in the ER. Water tanks and most plumbing is below waterline. I also use my boat year round and want it ready to go.
The outside air temperature this morning is around 32*F, the ER temp is 54*F. I know this as I have remote monitoring with thermostats in various boat locations, one being ER.
The ER air temp is maintained by the body of water it sits in which around here is about ~55*F. Notice the unheated ER temp is close to the water temp not the outside air temp.
NYC water temp shows to be ~50*F. Do you know the temp of your unheated ER?
I have to ask if winterizing is necessary to the extent being discussed every year?
 
how many gallons of fluids are needed for the engine and generator?

I use to use 6 gallons total for the Lehman 120, Westerbeke 4.4 generator and wash down system , and my fresh water system, doing as DM described above.
The engine was 3 gallons.
 
this is my first boat. I will live aboard for this winter, so initial plan is to use space heaters for heating, without winterizing anything. this way has proved dangerous when the pedestal breaker tripped once. it has been fine since then but I always have to take precautions.

NYC winter is colder than the Seattle area. the salt water in the marina does freeze at the coldest days. The marina has installed bubbler hose system, but that does not increase water temperature.

so I'm considering to winterize the engine and generator. as for the other components:

1. fresh water tank: rear tank is under aft cabin bed with an inlet at the transom port side. it's now empty. front tank should be under the dinette. I will leave them as is.

2. holding tank. just did a pump out this week. will use a porta potti. should I turn off the seacock and pour a gallon AF in through the waste deck fitting?

3. 3 reverse cycles AC units - v-berth, salon, aft cabin. will not use them. should I turn off their seacocks and winterize them?





Paul appears to be a new boater, or just new to trawler size boat and is exercising extreme caution. Kudos.

The following is for boats left in the water year round.
My boat(s) do not get winterized unless you count the airvents to engine room are covered leaving standing air (uncirculated) in the ER. Water tanks and most plumbing is below waterline. I also use my boat year round and want it ready to go.
The outside air temperature this morning is around 32*F, the ER temp is 54*F. I know this as I have remote monitoring with thermostats in various boat locations, one being ER.
The ER air temp is maintained by the body of water it sits in which around here is about ~55*F. Notice the unheated ER temp is close to the water temp not the outside air temp.
NYC water temp shows to be ~50*F. Do you know the temp of your unheated ER?
I have to ask if winterizing is necessary to the extent being discussed every year?
 
I use about 5 gallons on our Sp135 / GB 36. Maybe 3 gallons for the generator. I can do the whole boat with about 15 gallons. (Single engine) If you have mufflers, look for a drain plug and drain the water from each muffler first. Leave the plug out. Stop feeding the engines antifreeze when it drains from the muffler good and pink. No need to spend $$$ on filling mufflers with antifreeze. Be sure to bypass hot water heater, drain water tanks, etc.

I didn't find a drain plug in the engine muffler (picture 2). The Genny does not seem to have a muffler . The third picture shows the genny exhaust hose

IMG20231123114347.jpg

IMG20231123171927.jpg

IMG20231123172722.jpg
 
I didn't plan to winterize the potable water system as I will stay onboard for the winter. But I'd like to understand how to do it properly

1. If I get it correctly, I should disconnect the tagged clamp and insert the loose end into the AF jug?

IMG_20231123_185749.jpg

2. I think on the hot water tank, the red circle is the drain, red checkmark is the cold water input, green square is the hot water outlet. The outlet has a shutoff , but I don't see how to shut off the input hose. Maybe add a petcock valve?


IMG_20231123_190312.jpg


I don't see a washdown system in the anchor room.

Just want to confirm, no need to add AF into the holding tank, water tank, hot water tank, correct? (So you drained all tanks?)



You should use the pink RV/marine antifreeze. $4-5.00 per gallon at WalMart.

Do not put antifreeze in your fresh water tank. It will take about 5 gallons to dilute the existing water to 50% and it will take lots of flushing to get the taste out in the spring.

Instead, disconnect the suction hose to the pump. Replace it with 2-3’ piece of hose that you put the open end in a jug of antifreeze. Then run a bypass hose (sometimes all you have to do is turn a few bypass valves if it has been set up already) around the water heater and drain it down. Otherwise it will take another 5 gal to get to 50% and you will also have to flush lots of water through to get the taste out.

Use the fresh water pump to suck it up from the jug and run it until each fixture, hot and cold, runs pink. Takes just a few gallons to do the whole boat this way.

Also dump a cup or two of antifreeze in each drain to fill the P trap.

David
 
In many / most cases you can use a shop vac to suck water out of strainers for the ac/ heat. Then use the same vac to blow the water out of the lines. Double check that muffler for a small black drain plug around the bottom perimeter. I think mine is a 3/8 square head.
 
The propylene glycol over alcohol is spot on, alcohol will swell the impellers on any pump you run it through and absorbs into neoprene gaskets as well. If you winterize with the alcohol pink stuff you need to switch to nitrile impellers or pumps are prone to seizing up from the swelling. Including salt water toilets, don't ask me how I know...

Alcohol pink stuff will also set off your alarm for your propane system, as the alcohol fumes are detected by the sensor.
 
I think you will be at best very uncomfortable living aboard in NYC using space heaters. You have reverse AC. Use it.

To get a 30 degree F heat difference on a boat expressed in BTU multiply the interior volume in cubic feet by 15. Without knowing your boat's volume I'll guess you'll need 35,000 to 50,000 BTU to warm the boat from 38 F to 68 F.

To convert BTU to KW multiply by 0.00293. 35,000 BTU = 10.255 KW. A typical space heater on high is 1.5 KW. That's 6.8 space heaters. Drawing 85 AMPS at 120 Volts. If you need 50,000 BTU then the power demand is about 121 AMPS.

If I remember correctly from your boat lost AC power thread one 30 AMP circuit runs the reverse AC. The other 30 AMP circuit runs everything else.

In that thread you were cautioned to not run a constant load on a 30 AMP circuit higher than 24 AMPS. 24 AMPS at 120 Volts is 2.88 KW. 9832 BTU. Not quite 2 space heaters on high.





this is my first boat. I will live aboard for this winter, so initial plan is to use space heaters for heating, without winterizing anything. this way has proved dangerous when the pedestal breaker tripped once. it has been fine since then but I always have to take precautions.

NYC winter is colder than the Seattle area. the salt water in the marina does freeze at the coldest days. The marina has installed bubbler hose system, but that does not increase water temperature.

so I'm considering to winterize the engine and generator. as for the other components:

1. fresh water tank: rear tank is under aft cabin bed with an inlet at the transom port side. it's now empty. front tank should be under the dinette. I will leave them as is.

2. holding tank. just did a pump out this week. will use a porta potti. should I turn off the seacock and pour a gallon AF in through the waste deck fitting?

3. 3 reverse cycles AC units - v-berth, salon, aft cabin. will not use them. should I turn off their seacocks and winterize them?
 
Paulga - you might want to search on TF member "Lostsailor." He livesboard a Willard 36 in Boston. If memory serves he discussed his efforts to make a cozy boat s couple winters ago. He was pretty cheery about the results.

Not sure reverse cycle will be very effective once the water temp drops below 40 degrees or so. I'd go with a cheap Chinese forced air diesel heater and some insulation on your windows.

Peter
 
I use the 100. At high concentration it’s bacterial cidal. So get a twoer. Sterilize the fresh water system and protect from freeze damage. Also use it winterizing the watermaker for the same reason.
Problem is even after you drain water will remain in the low points so don’t trust draining alone. With 100 I don’t worry it has been diluted out so much as to be ineffective.
Yes a few extra bucks but way cheaper than freeze damage.
Have found shrink wrap keeps a boat warm. The passive solar is effective even with low angle sun and short days. Cut in a door you can reseal. Have opaque shades but pull them up on the sunny side when not shrink wrapped to get passive solar.
Don’t trust anything that is dependent on shore power. During the winter it may shut down from yard or grid failure or simply get unplugged. Would use a drip heater or hydronic as backup rather than just electric. Ok to use electric as first call but would have some form of backup.
 
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Paulga, I banged out my post #15 late last night. I have some more thoughts I'd like to share with you.

I've lived aboard off and on over the years in the Seattle area, a much more mild climate than NYC. We usually get a stretch of a few days to a week or two of sub freezing weather. I would say the typical overnight temps are mid 30 F to low 40 F. The last live aboard was purchased late in the year and I did not make heating a priority so I had to piece it together and stumble through that 1st winter. She was a 40 ft Tolly tri-cabin so a similar interior volume to your Marine Trader 40. She had a small base board heater in each cabin. I do not know their wattage. She had a propane catalytic heater in each cabin as well. I removed those because I don't trust them.

It became clear on the first cold night I was not going to be living aboard without more heat. Because it was already the heating season, like now, and I was already living aboard I didn't want to really tear into things and put in proper heating.

I discontinued use of the baseboard heaters and moved to space heaters with fans to better move the small amount of heat around. I purchased a knock off Espar air heater if I remember correctly 7,500 BTU. The combination was not nearly enough. I could heat one cabin to comfortable temperatures. But not even reach that level of comfort when the outside temps stayed below freezing for a few days.

I learned a lot that winter.

  • I don't like being uncomfortably cold all the time.
  • It really does take 35,000 to 50,000 BTU to comfortably heat a 40 ft boat. 50,000 is much better than 35,000 when it's cold enough there is snow on the decks.
  • The best way to get 35,000 to 50,000 BTU on a boat is to burn diesel.
  • Get creative in additional heating. I found a heated mattress pad a great help. It doesn't draw much power, turn it on 30 min before going to bed. If like many you spend some time in the evenings on the internet, watching TV or reading sitting in your favorite chair put a heating pad under your feet or get some electric socks.
  • During cold snaps close off on cabin, your choice. Best to inhabit the smaller cabin.
  • If you don't heat your engine room the cabin floor above will be cold, very cold.
A boat is a small living space. It's hard to get away from the windows. A single pane window lets a lot of heat out or cold in, depends upon how you look at it. Some liveaboards use stick on window coverings to help with that. I never tried it.

All of my live aboard boats have had a moisture problem in winter. Showering, cooking and just living add a lot of moisture to the air. A boat is not well insulated. Condensation is going to be a problem showing up as mold if you don't stay on top of it. Under mattresses, in lockers, drawers and cabinets. The best ways to minimize condensation are lots of heat and ventilation. Ventilation to the outdoors as well as leaving locker doors and drawers cracked open.
 
Portage Bay describes it perfectly.
Electric heat is the volume necessary is impossible.
Below 45f water temp heat pumps are marginal - useless below 40f.

There have been several threads on cheap diesel heaters. One of the more recent technologies developed for over the road truckers that installed correctly can be ok on a boat. Marine rated versions have been around a long time and well proven.
 
Did you have to worry about the transom shower water lines?


Screenshot_2023-11-23-19-46-23-71_92460851df6f172a4592fca41cc2d2e6.jpg

Paulga, I banged out my post #15 late last night. I have some more thoughts I'd like to share with you.

I've lived aboard off and on over the years in the Seattle area, a much more mild climate than NYC. We usually get a stretch of a few days to a week or two of sub freezing weather. I would say the typical overnight temps are mid 30 F to low 40 F. The last live aboard was purchased late in the year and I did not make heating a priority so I had to piece it together and stumble through that 1st winter. She was a 40 ft Tolly tri-cabin so a similar interior volume to your Marine Trader 40. She had a small base board heater in each cabin. I do not know their wattage. She had a propane catalytic heater in each cabin as well. I removed those because I don't trust them.

It became clear on the first cold night I was not going to be living aboard without more heat. Because it was already the heating season, like now, and I was already living aboard I didn't want to really tear into things and put in proper heating.

I discontinued use of the baseboard heaters and moved to space heaters with fans to better move the small amount of heat around. I purchased a knock off Espar air heater if I remember correctly 7,500 BTU. The combination was not nearly enough. I could heat one cabin to comfortable temperatures. But not even reach that level of comfort when the outside temps stayed below freezing for a few days.

I learned a lot that winter.

  • I don't like being uncomfortably cold all the time.
  • It really does take 35,000 to 50,000 BTU to comfortably heat a 40 ft boat. 50,000 is much better than 35,000 when it's cold enough there is snow on the decks.
  • The best way to get 35,000 to 50,000 BTU on a boat is to burn diesel.
  • Get creative in additional heating. I found a heated mattress pad a great help. It doesn't draw much power, turn it on 30 min before going to bed. If like many you spend some time in the evenings on the internet, watching TV or reading sitting in your favorite chair put a heating pad under your feet or get some electric socks.
  • During cold snaps close off on cabin, your choice. Best to inhabit the smaller cabin.
  • If you don't heat your engine room the cabin floor above will be cold, very cold.
A boat is a small living space. It's hard to get away from the windows. A single pane window lets a lot of heat out or cold in, depends upon how you look at it. Some liveaboards use stick on window coverings to help with that. I never tried it.

All of my live aboard boats have had a moisture problem in winter. Showering, cooking and just living add a lot of moisture to the air. A boat is not well insulated. Condensation is going to be a problem showing up as mold if you don't stay on top of it. Under mattresses, in lockers, drawers and cabinets. The best ways to minimize condensation are lots of heat and ventilation. Ventilation to the outdoors as well as leaving locker doors and drawers cracked open.
 
I have a DeWalt dcb517b wet dry shop vac
Are the steps like

Close seacock
Open strainer
Vacuum water out of strainer


Do you disconnect the water line before or after the pump to blow?


IMG_20231124_130347.jpg


In many / most cases you can use a shop vac to suck water out of strainers for the ac/ heat. Then use the same vac to blow the water out of the lines. Double check that muffler for a small black drain plug around the bottom perimeter. I think mine is a 3/8 square head.
 
No. Seattle rarely gets cold enough to freeze anything aboard the boat. And the shower sump drain line was under the aft head, a heated area.

If you have water or water drain lines in your lazarette living aboard in NYC you may want to keep some heat there.





Did you have to worry about the transom shower water lines?


View attachment 143802
 
my pic shows cabin side of the shower at the swim platform, not the shower in the aft cabin bathroom.

is lazarette the dinette area?



No. Seattle rarely gets cold enough to freeze anything aboard the boat. And the shower sump drain line was under the aft head, a heated area.

If you have water or water drain lines in your lazarette living aboard in NYC you may want to keep some heat there.
 
The lazarette is the below deck space immediately forward of the transom. It would be under the cockpit if your boat has a cockpit.
my pic shows cabin side of the shower at the swim platform, not the shower in the aft cabin bathroom.

is lazarette the dinette area?
 
The lazarette is the below deck space immediately forward of the transom. It would be under the cockpit if your boat has a cockpit.

my boat is a sundeck. the cockpit is on the flybridge directly above the lower helm in the main salon. what is immediately forward of the transom is the aft cabin that is under the sundeck.

the water lines in the areas remote from heat source are the concern.
the water lines against the aft bulkhead:

group 1 are to aft head hand wash sink
2 are to aft head shower and the sundeck sink
3 are to the transom shower (some sections are invisible so it's a guess)

I do shower stuff in the marina bathroom, so I'm thinking to add two separation values to shut off group 2 and 3. these lines are behind the genset so access is very tight. what model of valves should I buy?

IMG_20231124_145612.jpg
 
Those appear to be copper tubing with flare fittings. If I'm correct to do it right you're going to have to cut and shorten the tubing to create enough room for the valves. Slip the flare nuts over the tubing and flare the ends. You'll need a valve and two male pipe to mail flare fittings for each line. I prefer 1/4 turn ball valves, easy to turn, easy to see if they are open or closed.

You can cheat by finding some hose that the ID is a snug fit over the tubing OD, slide the hose over the tubing and hose clamp it. Then no need to flare which can be a challenge with old tubing. The valve will be fitted with male pipe to male hose nipples. A lot easier and you don't have to get everyting 'just right' because you can slide the hose along tubing to get it all lined up. The risk with that is the whole thing can come loose from pressure if not well secured.

I would look for another place easier to access.
I do shower stuff in the marina bathroom, so I'm thinking to add two separation values to shut off group 2 and 3. these lines are behind the genset so access is very tight. what model of valves should I buy?

View attachment 143804
 
I underestimated the difficulty. Thought it would be like undoing the nuts and plug in a valve. There is not enough access to cut the lines.

The starboard side of the genny seems to have more space, but still a lot of stuff in the way that are not straightforward to remove first


IMG_20231124_171437.jpg

IMG20231123180056.jpg

Those appear to be copper tubing with flare fittings. If I'm correct to do it right you're going to have to cut and shorten the tubing to create enough room for the valves. Slip the flare nuts over the tubing and flare the ends. You'll need a valve and two male pipe to mail flare fittings for each line. I prefer 1/4 turn ball valves, easy to turn, easy to see if they are open or closed.

You can cheat by finding some hose that the ID is a snug fit over the tubing OD, slide the hose over the tubing and hose clamp it. Then no need to flare which can be a challenge with old tubing. The valve will be fitted with male pipe to male hose nipples. A lot easier and you don't have to get everyting 'just right' because you can slide the hose along tubing to get it all lined up. The risk with that is the whole thing can come loose from pressure if not well secured.

I would look for another place easier to access.
 
I can't tell from your pics what the flow direction and tuning size are. You may be able to find enough wiggle room to open a connection at one of the flare joints and block off the flow with a flare plug. This may accomplish the same thing as a valve. Do yourself a favor and some tubing wrenches.



https://www.acehardware.com/departments/plumbing/pipe-fittings/brass-fittings/4503090?store=18305&gad_source=1&gclid=EAIaIQobChMIo5now_zdggMVvyqtBh2cLwr-EAQYASABEgJQxPD_BwE&gclsrc=aw.ds



I underestimated the difficulty. Thought it would be like undoing the nuts and plug in a valve. There is not enough access to cut the lines.

The starboard side of the genny seems to have more space, but still a lot of stuff in the way that are not straightforward to remove first


View attachment 143805

View attachment 143806
 
Thanks for the idea, it may work
Not so sure if the joints have not been turned for decades, what is the way to open it. Is this wrench good for this task?

If you cut the line, do you use a multi tool or reciprocating saw?


I can't tell from your pics what the flow direction and tuning size are. You may be able to find enough wiggle room to open a connection at one of the flare joints and block off the flow with a flare plug. This may accomplish the same thing as a valve. Do yourself a favor and some tubing wrenches.



https://www.acehardware.com/departm...VvyqtBh2cLwr-EAQYASABEgJQxPD_BwE&gclsrc=aw.ds
 
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No, that's a basin wrench. Get some tubing wrenches. Your pics show a lot of TEEs. Hold the TEE with a crescent wrench.



If you're going to cut and flare you MUST use a tubing cutter. The end must be square and no burrs. You'll need a flaring tool to make the new flare. You should be able to find kits with the tools needed. Don't cheap out, get good tools. Especially important when working in tight places



Get some new tubing and practice before you cut. It's not a tough skill to learn. Youtube probably has some good how to videos. Then consider the old tubing will be harder and more brittle. It may require annealing. Again, Youtube university will help you.


Another thing to look into is Shark Bite fittings. I've not used them. Read up, follow the manufacturer's directions if you go that way.
 
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