Antifreeze/coolant in fresh water cooled engine?

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orion50

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Is it advisable to mix in antifreeze ( as a corrosion inhibitor) in a fresh water cooled volvo?

Similarly is it better to leave the fresh water circuit full with strong dose of antifreeze over the winter rather than drawing it down? One would imagine a drained worm would be more prone to corrosion?
 
I use a good quality antifreeze mix left in the engine all the time. Dont buy the VP stuff, its cost is 10% product, 90% name.
 
Yes, normally 50/50 water antifreeze/corrosion inhibitor. Your handbook will tell you the spec and it is left in all year round.
 
Yes keep antifreeze in all year round.

Use the recommended concentration ... no more.

Change at the recommended interval.

Use the recommended type. Conventional low silicate or Organic acid technology (OAT) The former I expect.

Dont mix low silicate and OAT antifreezes.
 
Dose With Anti Freeze All Year Round

Unless there is something specific about Volvo engines then use antifreeze in the summer at your winter mix concentration just for the corrosion inhibition, if nothing else.

In the winter, unless you can drain down and be 100% sure that all fresh water has been removed then keep the fresh water system full of anti freeze. Small amounts of trapped fresh water only that freeze can cause a lot of damage. The water freezes from the outside inwards, hence you can end up with free water plugged at each end by an ice plug. As the ice plug continues to grow, the liquid inside the centre part exerts incredible force as it is compressed by the expanding ice and spits pipes, hoses, etc.

You must mix the anti freeze according to the correct ratios for the type you have. Excessive anti freeze concentration will actually freeze at a warmer temperature than water with the correct concentration of anti freeze.

In climates which are guaranteed to freeze it can be a good idea to blow compressed air through the fresh water circuit to dry out the insides. That is not required in the UK, just make sure that all the water is drained off or protected from freezing. Of course, trapped water with anti freeze wont freeze!

I left my boat out the water with anti freeze in the fresh water system all of last winter through the cold period. I understand that it was -6 continually for about a week, with the occasional -10 throughout the winter period. My engine was fine but the drinking water pipes at the low spots split open, despite draining down.
 
orion50 said:
Is it advisable to mix in antifreeze ( as a corrosion inhibitor) in a fresh water cooled volvo?

Similarly is it better to leave the fresh water circuit full with strong dose of antifreeze over the winter rather than drawing it down? One would imagine a drained worm would be more prone to corrosion?
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Yanmar are quite specific as to the grade of antifreeze to be used and that it should only be diluted with distilled or deionised water. I found a web link where they showed the corrosion effects of an engine using the wrong sort of antifreeze. Maybe Volvo is the same - would be worth checking.
I cannot remember what the specification was but I couldnt source it and ended up buying it from the agents Marine Power, I remember it didnt cost very much.
 
You must mix the anti freeze according to the correct ratios for the type you have. Excessive anti freeze concentration will actually freeze at a warmer temperature than water with the correct concentration of anti freeze
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.

Although the lowest freezing point for water ethanediol mixtures is around -51C at 70%. You would need nearly 90% before the Fpt rose above that for a 50% mixture.
 
VP2020 manual says use 50% mix all year round.
I assume that an ordinary automotive all glycol one (not ethanol or mixed) is OK, I've used CarPlan brand, is any expert going to tell me different?
It claims to be suitable for iron, aluminium etc etc and handily it changes colour according to the concentration.
I don't understand VicS's references to OAT and low silicate types - beyond my chemistry. (OAT is outside air temperature to me!!)
 
I assume that an ordinary automotive all glycol one (not ethanol or mixed) is OK, I've used CarPlan brand, is any expert going to tell me different?
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It depends which (of I think 3 ) Car Plan antifreezes you use.

Two are Organic Acid Technology (OAT) types and one is a conventional type, which they call IAT. Presumably meaning Inorganic Acid Technology.

Make sure you are using the correct type and you will be Ok.

They are all ethanediol (ethylene glycol) based.
In due course no doubt propylene glycol will replace ethylene glycol as a non toxic and environmentally more acceptable alternative.
 
VicS said:
Although the lowest freezing point for water ethanediol mixtures is around -51C at 70%. You would need nearly 90% before the Fpt rose above that for a 50% mixture.
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Thanks for clarifying the temperatures and concentrations as it puts the over dosing into perspective. I came across this a few years ago on a platform drilling rig that can be exposed to -40 degrees Celsius. The mechanics were quite diligent in measuring the cooling water anti freeze concentration for economy and protection.
 
In Ford cars at least, antifreeze changes are now going up to 10 years, approaching lifetime use! With oil changes for fully synthetics now up to 25,000, and brake fluid specification also improving, apart from filters, servicing on my cars has almost become a thing of the past! Some spark plugs are even good for 100,000 miles.

An eight year old engine I sold recently had 120,000 miles on the clock, no coolant changes, five oil changes and three plug swaps in it's life and it was like new. Fuel consumption, oil usage and cylinder compression all the same as when new. All I needed to do was top up the a/c and you could freeze to death.

OK, I'm talking about petrol engines but surely marine diesel service intervals need to get into the 21st century!

Richard
 
VicS said:
It depends which (of I think 3 ) Car Plan antifreezes you use.

Two are Organic Acid Technology (OAT) types and one is a conventional type, which they call IAT. Presumably meaning Inorganic Acid Technology.

Make sure you are using the correct type and you will be Ok.
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I had no idea there was so much to antifreeze - just like some people think batteries are simple and all the same!

What on earth do acids and silicates have to do with it? As you say CarPlan have 3 types now on their website, all different from what I used. I still have the can. It says 5 star all seasons antifreeze, BS6580, can be used in all vehicles,blah blah including aluminium blah blah. Doesn't mention ingredients other than ethylene glycol. I confess I've had it a few years but in a full foil sealed bottle so I assumed no deterioration. It may not be up to the latest VW spec as mentioned on the CarPlan website now but it's not as old as the VP2020 engine design! (It might be older than the actual engine - year 2002 :o - can't remember)

The VP manual just calls for "50% Volvo Penta antifreeze glycol", no other spec, so i thought I was OK using 50% this stuff.

VP website gives absolutely no idea of spec of their stuff - just calls it concentrated coolant.

Now totally :confused: do I need to change it?

Thanks!
 
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Now totally do I need to change it?
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Wouldn't think so although the old conventional stuff should be replaced every 2 years anyway.

that reminds me that antifreeze in my car is overdue for changing ( last done in 2003)

.
 
So if I read this correctly, the Carplan Blue Star antifreeze which is IAT and is a liquid coolant concentrate based on mono-ethylene glycol, containing corrosion inhibitors, will be suitable for a 3GM Yanmar which states it needs ethelene glycol?
 
Troubadour said:
I think this is relevant
http://fbhvc.co.uk/2010/01/27/antifreeze/
and this is too
http://www.opieoils.co.uk/pdfs/tech-articles/coolant-antifreeze.pdf
it says don't use the new type with copper.
My VP heat exchanger is copper so it indicates I should use the traditional stuff.
Phew!
(unless VicS knows different...)
(don't know about Yanmar I'm afraid)
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Yes those links support what i said. Interesting though that you should not use OAT with "yellow metals" . What do they make radiators and heater matrices etc from these days . Plastic ? Titanium?

Conventional IAT antifreezes then for everything unless the book says OAT.
 
first time I asked for "anti-freeze" in a Greek chandlers they looked at me in a very strange way as if I'd just escaped. There it is labelled "coolant additive" or "corrosion inhibitor" which, of course describes it's function in that climate. With the combination of dissimilar metals in any marine engine and especially Volvos, how could you contemplate NOT using the appropriate solution?

Chas
 
It is essential to use an appropriate corrosion inhibitor in the correct concentration. There are products which are inhibitors only which require about 5-10% and antifreeze containing inhibitors which require about 50% concentration.

The problem with antifreeze products is that they do reduce the capacity of the system to remove heat from the engine. This should be no problem, as the system should have been designed to take this into account. If however, the system is under performing, or the boat is in higher seawater temperatures than the engine was designed for, then the engine may be prone to overheating. Many people reduce the concentration of antifreeze in this situation, which is a mistake; the better option is to flush the system and switch to a inhibitor only, returning to an antifreeze product if there is any risk of frost.

The other classic problem of course is the topping up of leaking systems with water, gradually diluting the inhibitor/antifreeze.
 
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