How to winterize my sailboat (Volvo Penta MD7A), keeping it in Lake Geneva!

[okgood]

Hello,

I am looking for tips on how to winterize my Aloa 29 (with a Volvo Penta MD7A) in Lake Geneva, Switzerland.

It usually stays in the water in the winter, like many boats around here. I'm a relatively new boat owner. The previous owner didn't provide me with much helpful information, and I'm struggling to find a good (read: inexpensive) mechanic to help me.

If you have experience on this subject, then I would very much appreciate a detailed "to-do list" (including products). It usually only snows a few weeks per winter (in the city of Geneva, where the boat is), and the water doesn't freeze. See 3rd photo below of a typical scene following a heavy snowfall (I visited the boat that morning and brushed off all the snow).

Thanks in advance for any expertise you may be able to provide.

Kind regards,
Chris

[djmarchand]

Your weather seems similar to that of coastal North Carolina here in the US. In that area where I lived and kept my boat in the water for several years, I didn't winterize.


I did keep a small electric heater in the engine room set very low. This is the one I used https://www.defender.com/product3.js...1087&id=732071. It kept the engine room at 40 degrees F (about+5 C) even on cold nights that got down to the upper teens (about -9 C).


The boat was right outside my house, so I could check it after a cold night. If you have power at your slip, can hook up an electric heater and check it regularly this might be the way to go.


Otherwise winterize. Boats typically have several water systems that need winterization: engine raw water, head raw water, potable water and air conditioning raw water. There are lots of specific techniques, but basically you pump RV (recreational vehicle) pink antifreeze through all of these to displace the water. This is what I did when I kept my boat on the hard in New England where lows can hit 0 F or -18 C.


David

[S/V Illusion]

Originally Posted by djmarchand

.


basically you pump RV (recreational vehicle) pink antifreeze through all of these to displace the water. This is what I did when I kept my boat on the hard in New England where lows can hit 0 F or -18 C.


David

Antifreeze does not "displace" the water. Rather, it mixes with it and thereby decreases the efficacy of the antifreeze by raising the freeze protection temperature. If you did that, consider yourself lucky.

The proper technique is to remove as much water as practicable. Any residual amount will have space to expand if it freezes not causing any damage. Only then and if you feel compelled to do so should you add antifreeze minimizing the amount it is diluted by water.

[okgood]

Hi David,

Thanks for your response.

Unfortunately I don’t have power in my marina, only the 12v I make using my solar panel.

My engine is really basic. The only liquids inside it are the freshwater for cooling (sucked from the lake and spit out the exhaust), the oil and diesel fuel.

1) How do I pump anti-freeze through the engine - the main water inlet is in the lake? How much do I use (%)?
2) Is there anything I have to do to the diesel fuel (e.g., keep tank full, add anti-bacterial product)?

Thanks,
Chris

[okgood]

How do I remove the water? - do I close the inlet and watch the exhaust until no more water cones out? Do I keep the inlet closed?

Basically I’m looking for a to-do list.

Thanks!

[djmarchand]

Well, I must disagree with S/V Illusion. Pumping antifreeze through any water system does generally displace the water. Sure there is some back mixing which dilutes it a bit while the water is pushed through. That is why I would recommend using undiluted -50 deg F rated antifreeze which gives plenty of protection with a little bit of dilution.

For the engine's raw water system, what generally works is to close the thruhull and open the top of the strainer. Start the engine and pour antifreeze in the strainer and let the engine suck it up. Watch the exhaust outlet until you see foamy, pink antifreeze coming out and then stop. Leave the thru hull closed and you are done.

For potable water systems, you first have to pump all water out of the main tank. Then bypass the hot water tank by connecting the cold water supply to the hot water outlet tubing. This keeps you from filling the 6 gallons of hot water capacity with antifreeze which is very hard to get out in the spring, not to mention wasteful of antifreeze.

Then break the suction hose to the pump and connect a temporary hose from the suction to the bottom of a container of antifreeze. Start the pump and open each fixture, both hot and cold until you see pink antifreeze coming out. Then close that one and go to the next. Finally drain the hot water tank using the valve on it for that purpose.

The head is done similarly to the engine. First empty the holding tank. Then pour antifreeze into the strainer after closing the thruhull while pumping the head. When you see pink antifreeze in the toilet bowl then you can stop.

Finally pour a cup of antifreeze into each sink to fill the P traps as well as dump about a quart into the shower sump.

I suspect you don't have A/C so I will skip that one.

David

[S/V Illusion]

Originally Posted by djmarchand

Well, I must disagree with S/V Illusion. Pumping antifreeze through any water system does generally displace the water. Sure there is some back mixing which dilutes it a bit while the water is pushed through.

David

Having 3 decades of experience as a chemical engineer doing process flow design and construction, I won't debate opinions. Regardless of how much mixing occurs in a given system, some does which affects the efficacy of the antifreeze.


More fundamental is that you are using the antifreeze as a "tool" to push water which is a very expensive waste of expensive antifreeze. That's what pumps are for...


I used to routinely winterize our boat with 2 A/C units, 4 water tanks, 2 heads, 2 holding tanks, etc... when in New England with less than 3 gallos on antifreeze, most of that for the 2 heads.

[t588143]

The general rule is that you do not have to winterize your boat if the outside water does not freeze. If you want to be 100% sure then close the cooling water inlet valve and add antifreeze to the cooling water strainer. With the strainer cover off crank the engine untill all has gone. Repeat until your 1 ltr bottle of anti freeze is empty. Leave some level in the filter pot.

[Howler]

Hi Chris,

Looks like you’re in Port des Eaux Vives. I’ve left my boat in Lake Geneva (well Léman actually) every winter for the last 13 years. The lake never freezes, or only superficially in the worst of years. Most of your water is below the level of the lake and therefore isn’t at much risk of freezing. I basically do nothing, and even keep fresh water tanks full as I like to live on board occasionally during the winter. On really cold winters, I’ll squirt a little antifreeze into the raw water cooling circuit via the strainer. Relax and enjoy sailing on one of the most beautiful lakes in the world.

[hamburking]

Originally Posted by okgood

1) How do I pump anti-freeze through the engine - the main water inlet is in the lake? How much do I use (%)?
2) Is there anything I have to do to the diesel fuel (e.g., keep tank full, add anti-bacterial product)?

Here in Canada we have harsh, cold winters. Most boats are on the hard 6 months of the year, and the temps go down to 40 below for extended periods. Even worse are the freeze/thaw cycles before and after the deep freeze. Considering this, I would think of us as experts in winterizing our boats...especially considering that much of our "fleet" is from the 1970's and 80's.

Pull the engine water intake hose off at the shutoff valve of the through-hull. Stick it in a jug of antifreeze. Run the engine until the exhaust water is the same colour as the jug. As others have said, the antifreeze dilutes with the water already in the engine, so you need to flush out all the water. For your engine, I would guess 3 jugs (4 litres each). This puts antifreeze all through the engine and exhaust. Leave the antifreeze in there. Corrosion needs oxygen. If you drain the antifreeze, its replaced with air (oxygen) and you get condensation...perfect conditions for corrosion.

As a note, the antifreeze does in fact freeze if its cold enough...but it does not expand like water.

The Diesel fuel tank should be filled right to the top, to minimize condensation in the tank over the winter.

I personally did a lot of research on fuel storage additives...after having a bloom in my tank...and concluded that the best thing to do is add about 1/4 cup of GASOLINE to the DIESEL tank. Yes, you heard me!!! Mix well. This may be controversial and start a flurry of rants, but worked for me (after the bloom).

Elsewhere, as others have said, remove as much water as possible. Empty the fresh water tank, waste tank, and don't forget to check the hoses and empty those too. If you aren't sure, flush with antifreeze. The worst thing to deal with is a hot water tank. I wont' talk about that here. I also fill the head with antifreeze and pump about a jug through the hoses to the rubber parts don't dry out. After pumping and sponging the bilge totally dry, I dump a jug of antifreeze in the bilge and pump it through the bilge pumps (manual and auto).

Remember, a few jugs of antifreeze are a lot cheaper than a new engine.

Good luck!

[Dooglas]

Originally Posted by hamburking

The worst thing to deal with is a hot water tank. I wont' talk about that here.

Might as well. It has to be done, and is fairly simple with the right connections. Most of us install a bypass which allows the hot water tank intake and outlet to be closed. Once the tank is closed off, open the drain and leave the tank empty. Easy to do and completely reliable. The hot water system is then bypassed and RV antifreeze pumped thru the rest of the domestic water system.

[Captain Bucknut]

IMHO..... I would utilize some of the resource stuff you have around you. You may be able to put together (or it already exists) a group of owners at the marina and go about witerizing each other’s boats. In a weekend you’d be amazed at the number of boats you can get to. Ask around, I’m sur3 there are others that could help out.

[Nicholson58]

Originally Posted by djmarchand

Well, I must disagree with S/V Illusion. Pumping antifreeze through any water system does generally displace the water. Sure there is some back mixing which dilutes it a bit while the water is pushed through. That is why I would recommend using undiluted -50 deg F rated antifreeze which gives plenty of protection with a little bit of dilution.

For the engine's raw water system, what generally works is to close the thruhull and open the top of the strainer. Start the engine and pour antifreeze in the strainer and let the engine suck it up. Watch the exhaust outlet until you see foamy, pink antifreeze coming out and then stop. Leave the thru hull closed and you are done.

For potable water systems, you first have to pump all water out of the main tank. Then bypass the hot water tank by connecting the cold water supply to the hot water outlet tubing. This keeps you from filling the 6 gallons of hot water capacity with antifreeze which is very hard to get out in the spring, not to mention wasteful of antifreeze.

Then break the suction hose to the pump and connect a temporary hose from the suction to the bottom of a container of antifreeze. Start the pump and open each fixture, both hot and cold until you see pink antifreeze coming out. Then close that one and go to the next. Finally drain the hot water tank using the valve on it for that purpose.

The head is done similarly to the engine. First empty the holding tank. Then pour antifreeze into the strainer after closing the thruhull while pumping the head. When you see pink antifreeze in the toilet bowl then you can stop.

Finally pour a cup of antifreeze into each sink to fill the P traps as well as dump about a quart into the shower sump.

I suspect you don't have A/C so I will skip that one.

David

This is goo procedure.

We lived on the Great Lakes for many years. Minus 20 C is possible. The procedure is similar but we must haul out so we also leave antifreeze in the bilge. Pay close attention to flushing the engine from the strainer, this works. Failure here is disaster.

I used a shop vac to remove as much water as possible before adding the antifreeze. I also removed rubber impellers if the pumps were to remain idle. Good time to inspect.

As I recall from my visits to Zurichsee, winter was not so extreme. Check with your mates and ask what they do for in or out of the water storage. Pink RV antifreeze is non toxic. Auto antifreeze is toxic. Check local regulations regarding spring flushing into the lake.

[hpeer]

I have a MD7A I will winterize tomorrow.

I presume your MD7A is raw water cooled? It does not have a heat exchanger and a separate cooling water system. A few to, most do not.

The water circuit starts at your through hull, goes through a strainer, then through the transmission. A copper pipe runs from the transmission to the water pump, then under the manifold to the thermostat housing on the front of the engine.

The easiest thing to do is to:
Close the engine through hull
Remove the hose (assuming that there is not already a T connection for this)
Stick that hose in a bucket of water/antifreeze
Then run the engine until you have sucked through about 10l of the mix or you see it coming out the exhaust.
Shut down engien and replace hose.

My MD7A has a T fitting with a valve so that I can suck water from outside or from a bucket.

But also check local regulations about discharging antifreeze into the lake, it may be prohibited and carry a VERY stiff fine.

Best of luck.

[thruska]

If water doesn’t freeze you boat shouldn’t, however a heater in engine compartment is good insurance as aforementioned. A light on the power post maybe will show power at post , but w/o checking onboard you dont know if heater is on . Heater will help against condensation with compartment door open. Most heaters these days have thermostats.
Check or have someone check your boat often, especially if temp drops drastically.