anti freeze quantity in a TAMD61 and smokey engines

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60F

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I understand that a Volvo TAMD61 takes around 30 litres of antifreeze. When we drained off the engines a couple of weeks ago, we could only get about 15 litres out of the port engine, although the starboard gave up around 19 litres. I think the measurements were reasonably accurate. I assumed the differences to be due to the water heater on the starboard engine and possibly a difference in the height of the drain taps. We did not try to open the engines at the lowest point reasoning that this would just flood the engine compartments with a lot of sticky antifreeze that would get under the generator and battery trays and be difficult to get rid of. We then filled each engine with fresh water, ran them up, and drained three times - assuming that this would dilute the original antifreeze.

Having done this, we reasoned that we needed to ensure at least 50% antifreeze and so filled the engines with neat antifreeze. After getting the levels right, we seem to have managed to use around 40 litres of antifreeze (assuming that the new containers that we used were accurately full). So assuming that the water heater and associated hoses would take an additional 5 litres of coolant, we have put 40 litres on antifreeze in engines that will take around 65 litres! An average of around 61% instead of the recommended 50% - possibly more as presumably some of the original antifreeze would still remain (and probably more in the starboard engine due to the impact of the heater).

I think I need to remove some of the coolant in each engine and replace it with a few litres of water to try and get the water / antifreeze mixture to around 50% - and then presumably use a strength tester after the engines have been run up again to full operating temperature. However, before I do this can anyone advise whether you can really have too much antifreeze in an engine (as it also ups the amount of anti corrosion inhibitors as well - which may be a good thing). I understand that a high level of antifreeze makes the coolant less efficient at cooling, but I am unsure whether this makes a minor difference or a huge difference and do not want to take her out to sea until I know if I should reduce the antifreeze a little or not.

One final thought, during the oil change we used some Morris oil that was recommended. It seems in line with Volvo recommendations, but she does seem smokier than last year. She has not yet been properly warmed other than to change oil and water. Is this normal for engines that have been unused over winter and likely to go away, or do I need someone to have a good look at them before we put them under any stress. My understanding had been that provided the oil was within spec it was more important to change it regularly than to up the spec of the oil.

Any thoughts on both matters would be gratefully received.

Many thanks.
 
You are right in thinking that water is a more effective heat transfer medium than ethanediol
The specific heat of water at 4.19 KJ/Kg.K is nearly double that of ethanediol at 2.36 KJ/Kg.K although since in an a engine cooling system you would be considering volume flow rather than mass flow you would have to correct that for the density difference ( water 1000Kg/m³, ethanediol 1097Kg/m³)

A 50% solution will give all the frost protection you are ever likely to need. The freezing point of a 50% ( by volume) solution is -37C

As far as i know the main objection to high antifreeze concentrations is the detrimental effect on flexible vane pump impellers . That is something of concern when winterising directly cooled engines or the raw water circuit of indirectly cooled ones. I assume your freshwater cooling circuit does not have a flexible vane type of pump?

I'd not split hairs over the antifreeze concentration. How fussy are you about it in your car? A quick check with a simple tester would not be bad idea though. ( about £2 from Halfords.)

Ensure though that you use the correct type of antifreeze for the engine and that you do not mix conventional low silicate antifreeze with the organic acid technology (OAT) type
 
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Thanks. I think I will feel happier when I have checked it and got the right mix. At least next time around it will be easier as I now know exactly what is in there and can keep an accurate record of exactly the quantity that comes out.
 
The cooling system is approx 30 litres

It says so in the owners manual ( page 45 and 67)

You can download a manual if you have mislaid yours from HERE
 
Too much anti-freeze used to be a problem with impellor pumps vanes, but not any more. Modern materials and improved anti-freeze means this is now longer a problem like it once was.
 
In addition:

Anti freeze is a misnomer as its main function is corrosion inhibition between dissimilar metals and other metallic or other components, preventing freezing is a secondary function.
Having an excess in will prevent corrosion more effectively, and for longer; the thermal transfer rate becomes insignificant if there is less internal corrosion as it will transfer heat more effectively than a corroded water jacket.

Basically its a case of 6 or two 3's.
 
Just nearing completion of re engining a powles 46 with 2 second hand 61as, drained the motors at the block, heat exchangers and exhaust manifold, and oil cooler pipes.

A 50/50 mix took approx 15 ish litres per engine of neat a/f and water to refill, the brown water that came out was very sludgy, just shows why volvo reccomend to changethe coolant every 2 years.

On the smoke side the motors started well to say they had been stood for a number of years, injectors were removed for testing, 11 out the 12 were hosing/poor atomisation, so new nozzles fitted, the smoke on start up now is a lot better but not a match to common rail tech.
 
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