More matematical then technical but here it goes;
This weekend I drained the coolant 10 times till I knew it was all water, it took a long time to warm up everytime and drain.

My question is now that I know it's all water and all I can drain out is 2 litres, I will have 4 litres of water with 2 litres of coolant, resulting with a 66.6666% water and 33.3333% coolant based on Capacity of 6 Litres.

Once I have this mixed up really good, if I drain 2 lires of this 66.7/33.3 ratio and add 2 litres of straight coolant, will I exceed the 50/50 mix recommended?

Any math genius out there? I'm too old to figure that one out.

Thank you,
Al

 

Yes, doing that will result in more than 50% coolant. To get a 50/50 ratio, drain 2L of the 66%/33% initial mix, and then add 1.67L of coolant and 0.33L water to top up.

The logic:
In the initial mix, you had 2L coolant and 4L water. Draining 2L of that removed 0.66L coolant and 1.33L water (leaving 1.33L coolant in the engine). A 50/50 mix would be 3L coolant, so you need to add 3-1.33=1.67L of coolant.

 

Thank you that is what I was looking for, I was guessing 1.5 would be close but not exact, 1.67 is more accurate.
I got 7 years out of the original and it looked and tested as new, I wish I had tested the PH.
The reason why I got 7 years, I only have 4500 miles on the car and didn't see it for the last 2 years, but I got really worried once I remembered the coolant was not replaced yet.
The battery was not connected for most of the time, I'm not sure if that has anything to do with it, having no current at all moving, I'm no chemist but I heard corrosion and electical current can speed up the process, no idea of that is true or not.

Al