Engine winterizing

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altinr

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Jul 20, 2019
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How do you tell which RV/MARINE nontoxic propylene glycol antifreezes are suitable to winterize the raw water circuit of diesel engines?

Also, is there an easy way to put the antifreeze in at the water strainer ... removing the hoses is always suvh a struggle!
 
Welcome aboard. I use -100 rated antifreeze. I get it at WMP because they will ship it for free. I use the -100 because I can test the output with a reflectometer. Some will say just wait until the color comes out of the exhaust. But when I first see color it only tests down to about +20 degrees so I keep putting in antifreeze until it tests to -20 degrees.

I use a Sea Flush adapter to winterize my main engines. All I have to do is remove the top of the strainer and bungee the Sea Flush adapter funnel into the strainer. It comes with a hose that inserts into the funnel and I use a 5 gallon bucket to put the antifreeze in. It literally takes me 5 minutes to winterize an engine. What takes the time is pouring the antifreeze into the 5 gallon bucket. No affiliation with Sea Flush but I love it. Seaflush.com
 
I use one of these. It works great if you have a Groco filter. The Sea Flush is good, too. I've also just taken the cap off the raw water strainer, closed seacock and simply poured anti freeze into the strainer. That requires help or the ability to reach the start/stop switch from the engine - but it works.

I believe the degree you winterize to is dependent on location (no kidding). I was much less concerned when I was in Florida. Here in VA I use -20 usually, but I've used lower temp anti freeze when I could get it cheap. If I were in Maine I'd go with -100. I think where you and I are (central East Coast), the weather is pretty forgiving and -20 is fine.
 

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I simply used a large funnel into the strainer. With the funnel filled it provided just a little more head pressure. Then have the "mate" look for coloration in exhaust or just pour in 3 gallons (single engine). Also need a person to start and stop engine. Do not forget to do the same for your AC units. Also, your water system and water heater tank, windscreen washers and frig/freezer/ice-maker-- except Raritan ice-makers do not do well with antifreeze - best to just try to drain/blow out. Also need to flush bilge pumps and make sure freshwater pump is flushed. In case you have a washer/drier, do not forget that!!
 
I use the -50/60 propylene glycol based antifreeze. I generally put 4-5 gallons through the system which is enough to thoroughly flush my cooling system. I have never had a problem here in Maine where winter temps get down to -5 F or so.
 
The RV "drinkable" antifreeze is needed in the potable water system , but not in the rest.

The ancient green stuff is better in machinery as it has anti rusting chemicals , and water pump lube .

You can't discharge it over the side as was done in the past.

The only hassle with the RV stuff is the pipes are best when left full , as with air contact it will dry out and you will flush "forever" in the spring to get rid of the color and taste.
 
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Fully draining the system is best but if you need to use anything then ethylene glycol is the safest for plastics, rubber gaskets and seals.

I have had great results with both a wet vacuum and compressed air in clearing both potable water systems and engine lines that are not easily gravity drained.

You will need to recover any ethylene glycol that you put into the system at spring commissioning.
 
I use one of these. It works great if you have a Groco filter. The Sea Flush is good, too. I've also just taken the cap off the raw water strainer, closed seacock and simply poured anti freeze into the strainer. That requires help or the ability to reach the start/stop switch from the engine - but it works.

I believe the degree you winterize to is dependent on location (no kidding). I was much less concerned when I was in Florida. Here in VA I use -20 usually, but I've used lower temp anti freeze when I could get it cheap. If I were in Maine I'd go with -100. I think where you and I are (central East Coast), the weather is pretty forgiving and -20 is fine.

I use one of those on my generator and the A/Cs. But my main engines have really big strainers that are not Groco so the Sea Flush works great. I fill a 5 gallon bucket with antifreeze, I don’t think that I could pour it fast enough into a plain funnel since the main engines will suck in the 5 gallons in less than a minute.
 
Also, is there an easy way to put the antifreeze in at the water strainer ... removing the hoses is always suvh a struggle!

Here's what I use...
Rubber bung w a threaded barb fitting inserted into the hole. Hose to suck from jug or attach to a larger container.
Bung stoppers available in different sizes for different strainers.20160911_115734.jpeg20160911_125040.jpeg
 
To winterize Datenight I made this get up for my Groco strainer;

1. Drilled a 2" hole in a 5 Gallon bucket

2. Attach 2" PVC slip to thread adaptor to bucket, threaded end in bucket, trim off extra thread so it portrudes as little as possible into bucket

3. Add a 2" PVC "riser" to slip connector, you will have to experiment with length, mine was about 6"

4. Another slip to thread adaptor. This one threads into the top of the Groco strainer.

To use thread first adaptor into bucket, the second into the strainer, add your length of pipe in between. Fill the bucket with as much antifreeze as you need. I started with about 4 gallons. I usually poured about 2 more in because antifreeze is cheap and a Cummins 5.9 QSB is expensive. Had assistant start engine and shut off.

Same for generator and AC

For potable water 5 gal bucket with hose out the bottom. Made needed fittings so I could attach it just after the tank which was drained.Bypass water heater

Fill bucket with antifreeze, run onboard potable water pump untill pink came out all spigots, window washers, and fresh water wash down. That went with the boat as well.

Took a little time to chase parts and make the two get ups but they made winterizing easy.

Wish I could post a picture but the contraptions went with the boat when we sold it.

Rob
 
All you folks winterizing your engines, is your boat in or out of the water? We live aboard in Maryland, south of Annapolis. This winter will be our third. Before that, the boat stayed in the water with no one aboard for one winter. I did not winterize the engines. They did not freeze. The coldest it ever got in the engine room was 35 degrees but that was during a 7-day period of extremely cold temps (5 degrees) overnight. Think about it. Even with occasional surface ice of several inches, the hull is sitting in water that is above freezing temperatures thus insulating the below waterline environments analogous to an igloo. Yeah, I know, but what if, cheap insurance and all that. If you are concerned just drain the raw water circuit and call it a day. Even with some residual water, IF it were to freeze, expansion damage would not occur. As for other systems (fresh water supply, toilets) I would winterize if not living on board.

I'm ready for your slings and arrows. Fire away.
 
Where... When?
I do all systems in the water ahead of time. Raw & fresh water, AC, head using the set up pictured above.
The yard opens those sea cocks after blocking to release the water trapped in the valve ball.

Engines req'd to get boat to winter storage yard and for them to get it to haul out slip.

I have the yard do engine and gen and they do it right in the lift when pulled... drum of AF mounted on the lift w gravity feed to valve & toilet plunger. Done using the thru hull. Not all that expensive, cheap insurance.

Many OK ways, that's mine.
 
I run antifreeze thru my strainers to do my engine manifolds, risers , heat exchangers as my engines are closed cooled. Do the same for the generator. On the domestic water side I drain the water tanks, no antifreeze, also bypass and drain the hot water tank, no antifreeze, then I air blow all lines through each tap, shower, head, then using a T fitting at the pump suction I pump propylene glycol based antifreeze through all the lines etc. Then I air blow again. Sounds complicated but really can all be done in about a half hour.
 
All you folks winterizing your engines, is your boat in or out of the water? We live aboard in Maryland, south of Annapolis. This winter will be our third. Before that, the boat stayed in the water with no one aboard for one winter. I did not winterize the engines. They did not freeze. The coldest it ever got in the engine room was 35 degrees but that was during a 7-day period of extremely cold temps (5 degrees) overnight. Think about it. Even with occasional surface ice of several inches, the hull is sitting in water that is above freezing temperatures thus insulating the below waterline environments analogous to an igloo. Yeah, I know, but what if, cheap insurance and all that. If you are concerned just drain the raw water circuit and call it a day. Even with some residual water, IF it were to freeze, expansion damage would not occur. As for other systems (fresh water supply, toilets) I would winterize if not living on board.

I'm ready for your slings and arrows. Fire away.

It takes very little time to suck the fresh water system dry by opening one tap at a time starting with the furthest tap from the vacuum - for us the vac is after the fresh water pump. We do that cycle twice and no water is left.
We have been doing this in the NE (from LI to Kingston NY) for more than 30 years now. We also drain the waste system and add some antifreeze before pumping that out as well. Engines are similarly done by draining but if in the water in MD. with power I would be tempted to just run the lower wattage block heaters that we had.
 
All you folks winterizing your engines, is your boat in or out of the water? We live aboard in Maryland, south of Annapolis.

I'm ready for your slings and arrows. Fire away.

Catalinajack - no slings or arrows, but a question. We are in the same climate and I'm winterizing in the water this year. I will winterize everything because I'd rather not worry about ER temps dropping below freezing and I'm not onboard all the time.

But I'm curious if you have found it necessary to use a bubbler or ice eater to protect the hull? I'm south of you in Reedville, VA, but we have essentially the same weather and my river ices over every couple years for a few days.
 
Move the boat south for the winter. Then you won't need to worry about anti-freeze :)
 
I am in Alaska and the boat remains in the water year round.

I keep the boat heated and stay on it in the winter but winterize the engines anyway in case of heater failure. I also seal up my engine room from the outside by blocking the air intakes which helps ambient temperatures ALOT.

First off a boat in the water will rarely if ever see engine room temperatures drop below freezing. That’s because it is surrounded by water which is above freezing.

As an added protection I run 7 gallons of -50 rv antifreeze through the engines. I buy the good stuff aw West Marine when it goes on sale.

To do this I take the lid off of the perco sea strainers and pump from a 5 gallon bucket into the sea strainer while the engine is running.

Easy peasy.

Two more winters till retirement, then the boat moves south with me on it for the winter.
 
Like kevin says ... heat the boat.

And if the power fails it will be a long time to quite awhile before any freezing to be concerned about happens.
Most of the time I’ve been on this forum we lived in Alaska and relied on several electric heaters. It’s been well over 10 years and I doubt if it’s been much below 40 degrees anywhere in the boat.
However, we were hauled out for two years and were fully winterized then.
Much of what’s on this thread smacks of “bigger is better” in anchoring.
 
Just some mitigation here, I understand that even in Alaska you may not have to winterize but mainly because you are sitting in an oceanic body of water. Up here in fresh water on a river you cannot stay in the water as the whole surface is hard frozen.

L
 
"But I'm curious if you have found it necessary to use a bubbler or ice eater to protect the hull?"

I lived aboard for almost 23 years , most in the NYC area, where 0-F is uncommon but does happen a couple of times most winters.

I prefer to let the hull freeze in solid as it does no harm to a GRP boat.

The bubbler makes living onboard Hell as you get noise like being in a fish tank 24/7.

The fear on wood boats was that as the boat froze in the water in the cotton would be pulled loose , the boat held up by the ice , only to leak large when the ice melted.

In spring with the ice melting its good practice to break up the ice in the slip so the boats motion does not grind off paint at the WL.
 
Catalinajack - no slings or arrows, but a question. We are in the same climate and I'm winterizing in the water this year. I will winterize everything because I'd rather not worry about ER temps dropping below freezing and I'm not onboard all the time.

But I'm curious if you have found it necessary to use a bubbler or ice eater to protect the hull? I'm south of you in Reedville, VA, but we have essentially the same weather and my river ices over every couple years for a few days.
No bubbler. No way you are going to get ice thick enough to damage yoir boat. I've seen ice four inches thick in this marina with a hundred boats in the water. No reports of damage.
 
"But I'm curious if you have found it necessary to use a bubbler or ice eater to protect the hull?"

I lived aboard for almost 23 years , most in the NYC area, where 0-F is uncommon but does happen a couple of times most winters.

I prefer to let the hull freeze in solid as it does no harm to a GRP boat.

The bubbler makes living onboard Hell as you get noise like being in a fish tank 24/7.

The fear on wood boats was that as the boat froze in the water in the cotton would be pulled loose , the boat held up by the ice , only to leak large when the ice melted.

In spring with the ice melting its good practice to break up the ice in the slip so the boats motion does not grind off paint at the WL.

FWIW - in our areas of winterizing we have seen hulls cut up pretty well by ice when there are no bubblers. Seems to be area specific , this was in both the Northport Huntington area.
 
No bubbler. No way you are going to get ice thick enough to damage yoir boat. I've seen ice four inches thick in this marina with a hundred boats in the water. No reports of damage.

Must be very area specific - I have seen hulls cut up pretty bad at the waterline by ice in the Norhport and Huntington areas of LI NY.
 
Must be very area specific - I have seen hulls cut up pretty bad at the waterline by ice in the Norhport and Huntington areas of LI NY.

I think this is very true - all weather is local. In my case, I have an aluminum hull - so cosmetics is not a big issue, but ice can cut aluminum fairly easily with enough wave action...and since I'm on a brackish river with commercial boats, there is always wave action when they are on their way out to the Bay.

I think for my purposes, having a bubbler on hand that I can use for those years where there is an extended cold snap is far better than just letting the boat ice in.

Same with engine winterizing - having an aluminum hull that doesn't retain heat along with a shallow draft means I have a lot of engine room above the waterline and exposed to air temp and a small amount below the waterline and insulated by water means I need a system to ensure the raw water stand pipe doesn't freeze.

Engines will be winterized, so I'm covered there, but I'd feel better having a positive plan for the standpipe. That's why I'm always interested in what people in our area have found from experience - but I always try to apply their experience to my situation.
 
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