Antifreeze type and volumes

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Hi all

Grateful for steer: is the antifreeze to winterise the freshwater system (propylene glycol) the same as for blackwater system and also for engine?

And any tips on volumes? Engine is Volvo penta, and needs to accommodate the calorifier. More significantly regarding freshwater, yacht is 44 feet with water tanks bow and stern, plus heads bow and stern.

Thanks!
 
Always use the recommended Volvo Penta antifreeze for the engine, it contains corrosion inhibitors.

You don't say where the boat is, or whether it's ashore for the winter. This is crucial info if you want sensible answers. My boat is afloat over winter in the UK and I don't use antifreeze in the water tanks, nor do I drain them. All I do is leave the water taps open when I leave the boat.
 
Always use the recommended Volvo Penta antifreeze for the engine, it contains corrosion inhibitors.

You don't say where the boat is, or whether it's ashore for the winter. This is crucial info if you want sensible answers. My boat is afloat over winter in the UK and I don't use antifreeze in the water tanks, nor do I drain them. All I do is leave the water taps open when I leave the boat.

You don't put AF in the potable tanks, you drain them. If you put AF in them it is very hard to flush in the spring. Instead, add valves and a hose to suck it only through the pipes.

Remember, pouring AF in the toilet only winterizes 1/2 the system. You need valves on the suction side to get the other half. Obviously, pump the black water tank empty.
 
Hi all

Grateful for steer: is the antifreeze to winterise the freshwater system (propylene glycol) the same as for blackwater system and also for engine?

And any tips on volumes? Engine is Volvo penta, and needs to accommodate the calorifier. More significantly regarding freshwater, yacht is 44 feet with water tanks bow and stern, plus heads bow and stern.

Thanks!

Use a propylene glycol antifreeze if necessary to protect your domestic freshwater system....... a good source would probably be a caravan, or motor caravan, equipment suppliers..... use at the recommended concentration. It is to all intents and purposes non-toxic to humans and other mammals but just as toxic as ethylene glycol towards aquatic life so dispose of it responsibly.

Use either a conventional, low silicate, or an OAT type of ethylene glycol based antifreeze for an indirectly cooled engine depending upon the engine manufacturers recommendations. Recent VP engines use the OAT type , which will be specified in the manual, while older ones use the conventional type ( VP antifreezes are yellow or green but read the labels on other brands , don't just go by the colour.
Generally don't mix conventional and OAT antifreeze use the same type as at present. If in doubt seek out an antifreeze which is compatible with both. Special ( expensive) cleaning procedures are required if it is necessary to change from one type to the other, especially if changing from conventional to OAT

Usually a 50% dilution of the concentrate is called for. There is no advantage in making it more concentrated than 50%.
In hard water areas, or if the water supply is high in dissolved solids, the concentrate should be diluted with distilled or deionized water..... alternatively buy it ready diluted.
 
... It is to all intents and purposes non-toxic to humans and other mammals but just as toxic as ethylene glycol towards aquatic life so dispose of it responsibly....

Not exactly. It is toxic to marine life only in specific ways.
* High COD. Like any organic material, biodegradation pulls oxygen from the water. So does a pile of fallen leaves.
* Toxic, sort of like drinking alcohol is at high concentration.If you look at the SDS LD 50s, you will see the required amount is huge. The US Fish and Wildlife Service lists EG as effectively non-toxic to fish.

That said, recycle if you can. But this is nothing like bottom paint, and in fact, practically any soap.
 
I think I'm simply reiterating Vic comment - I believe the new Volvo engines, the 'D series, use a yellow AF, previous models, that ended with the MD series, use green. Volvo have their 'own' AF - as Vic says read the labels.

Jonathan
 
Since the OP mentioned winterizing the freshwater system, it might be worth mentioning glycerine based AF as a non toxic and environmentally friendly (and plant based) alternative.
This has been available for a couple of years where I am based.
I am using it this winter for the first time in the raw water circuit of my indirectly cooled engine, diluted 50/50. Previously I used propylene glycol based AF for this.
NB the type I am using it is not suitable for the engine's fresh water circuit, as it is not compatible with high temperatures.

https://www.vake.se/en/organic-antifreeze/
 
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I think I'm simply reiterating Vic comment - I believe the new Volvo engines, the 'D series, use a yellow AF, previous models, that ended with the MD series, use green. Volvo have their 'own' AF - as Vic says read the labels.

Jonathan

It may not be quite that simple, although I think you are probably right about D series using the yellow " coolant"

ITYWF that the green "antifreeze" is specified for early versions of the MD 2010 -2040 range whereas the yellow " Coolant" is specified for the later versions. I suspect the important consideration will be to use the same type as the initial fill although there may have been a change in the materials used , in for example the heat exchanger

There was at one time an applications list on VP's website but that disappeared some while ago when the website was updated and "improved"
 
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It may not be quite that simple, although I think you are probably right about D series using the yellow " coolant"

ITYWF that the green "antifreeze" is specified for early versions of the MD 2010 -2040 range whereas the yellow " Coolant" is specified for the later versions. I suspect the important consideration will be to use the same type as the initial fill although there may have been a change in the materials used , in for example the heat exchanger

There was at one time an applications list on VP's website but that disappeared some while ago when the website was updated and "improved"

The D1 D2 Operator's Manual explains which coolant to use. For these engines, it's the yellow OAT Volvo Penta Coolant VCS.
 
Thanks everyone. Tips on how much I need to buy, please? Would be a bore to run out halfway through! Thanks
 
Thanks everyone. Tips on how much I need to buy, please? Would be a bore to run out halfway through! Thanks

The Operator's Manual for your engine will tell you the engine's coolant volume, add a bit more for the calorifier circuit.
 
Thanks everyone. Tips on how much I need to buy, please? Would be a bore to run out halfway through! Thanks

It depends on the cooling circuit capacity of your engine, plus whatever extra is contained in the calorifier heating coil and connecting pipework

Read the owners manual for the engine and add on an estimate for the calorifier etc. You will need the full vaolume if you are using ready diulted antifreeze or 50% of it if you are using concentrate. Dont forget the same volume again of distilled or deionised water for dilution.

Assuming you will empty your domestic water system ( you will have to empty it anyway in the spring if you add propylene glycol to it) be sure to drain the water from the pressure pump , strainer , accumulator, taps and shower fittings and the freshwater side of the calorifier and expansion tank.
 
Read the owners manual for the engine and add on an estimate for the calorifier etc. You will need the full vaolume if you are using ready diulted antifreeze or 50% of it if you are using concentrate. Dont forget the same volume again of distilled or deionised water for dilution.

The OP still hasn't said what engine he has, or whether he needs yellow or green antifreeze. However, if he needs the yellow Volvo Penta Coolant, VP say the concentrate should be diluted 40% antifreeze/60% water.
 
The OP still hasn't said what engine he has, or whether he needs yellow or green antifreeze. However, if he needs the yellow Volvo Penta Coolant, VP say the concentrate should be diluted 40% antifreeze/60% water.


It should be at least 40% to ensure an adequate concentration of inhibitor. The same applies to the green type. Neither type should be used at concentrations greater than 60%
 
Usually a 50% dilution of the concentrate is called for. There is no advantage in making it more concentrated than 50% ,,,

... and indeed to high a concentration of antifreeze can be as bad as too low. A quick google turns up this graph for ethylene glycol in water, which accords with my memory but which I won't absolutely vouch for.

main-qimg-c51ab2e832fcaf16641c971f031fdd27
 
... and indeed to high a concentration of antifreeze can be as bad as too low. A quick google turns up this graph for ethylene glycol in water, which accords with my memory but which I won't absolutely vouch for.
]

Thanks . I thought it probably formed a eutectic but I could not find the graph.

ITYWF as the % ethanediol increases the heat transfer properties deteriorate and the pumping requirements increase. Several reasons therefore to limit the concentration.
 
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Thanks . I thought it probably formed a eutectic but I could not find the graph.

I can't find a good source for a phase diagram, but this appears several times on the internet as pat of a cheating student's request for help with an assignment:

aTuSy1u.png


Couldn't really be a more classical eutectic!

ITYWF as the % ethanediol increases the heat transfer properties deteriorate and the pumping requirements increase. Several reasons therefore to limit the concentration.

Excellent points.
 
I think I'm simply reiterating Vic comment - I believe the new Volvo engines, the 'D series, use a yellow AF, previous models, that ended with the MD series, use green. Volvo have their 'own' AF - as Vic says read the labels.

Jonathan

No this isn't neccessarily the case. My D series has Volvo Green colour in it. Volvo's very clear advice is to replace with the same colour as you just took out. Apparently they don't mix at all well. Obviously if you are simply winterising the seawater side then use whatever you want as it will be quickly flushed through by seawater in the spring.
 
It's a D2 55, thanks everyone for helpful advice and even some science. Crikey you folks are knowledgeable!

Still not sure how much propylene glycol I am buying for freshwater system ☺️ thanks.! Yacht 44 foot, aft and rear tanks, two heads both with shower.
 
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