Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Recommended anti freeze strength

Just fitted a nice new Sifab aluminium radiator to my Roadster and all went well on the fitting. When I came to filling it with 50% water 50% Ford premium antifreeze I stupidly poured in the 6 litres of new antifreeze first to be followed by the 5 litres of water for the 11 litre total volume of the engine. On pouring in the 6th litre of antifreeze it became apparent that the coolant was full. I had obviously not managed to get all the water out of the block and heater presumably as the thermostat had not opened. I should have realised this as the volume in the bucket of old coolant measures about 6 litres.
I ran the engine up to temperature and the thermostat opened and the fan also came on so all ok. There were a few air bubbles to come out.
I now have an engine with 6 litres of new antifreeze and 5 litres of probably old 2 litres anti freeze and 3 litres water. (I had topped up a bit with water). If my maths is correct this adds up to a 73% antifreeze level rather than the recommended 50%.
What should I do? Leave it as it is or drain a bit off and top up with water to get a 50% mixture. The maths might get a bit more difficult!!
Does over strength anti freeze affect cooling or attack the engine?

Personally I wouldn't worry too much about this. The level will probably drop a bit after the first long outing.

If it bothers you then drop a litre and fill with water.

Yes you have a bit too much antifreeze in the coolant but as you are in Edinburgh rather than in Braemar the reduction in freeze point of the coolant will not be an issue.

The main issue would be the you have a good amount of new antifreeze with new corrossion inhibitor and a reasonable amount of coolant mix with worn out corrossion inhibitor.

Unless you know the maker of the original fill at the factory and that is compatible with the make you have refilled with then you should flush it all out by filling and draining a good few times but always running to the thermostat is open on each flush.

Would I do that, probably not!

The strength reccomended depends on the climate. Without checking the details should be on the container.
Your 73% is too high, as I think up to 50% is advised for cold climates (Scandinavian winter type). A minimum strength is also advised to maintain anti-corrosion properties.

As an aside.....make sure you use the right type of antifreeze....mixing wrong types can cause reactions/sludge. The types are OAT and non OAT.
If in doubt, flush it out!

As said you will probably get away with it but…… I don’t know anything about your engine but my aluminium Duratec is designed to run normally quite hot so I would use an antifreeze tester and check the concentration. If it was as high as you say I would dilute as the more concentrated solution would be less effective at removing the heat from your engine. So there is a small risk of heat related stress and damage.

You should have used Evans Waterless.........

Noooooooo!

Not Pygmalion likely!

Thanks all for your observations. I may take a couple of litres out and top up with water. I have not done the maths but I think that would be about right.
I have not mixed different antifreeze as they are both Ford premium and I had the good sense to mix a sample first to ensure they were compatible. Ford apparently only make / sell one type of anti freeze now.