coolant refill question

[marshall]

My basic goal was this: I'm experiencing no problems with overheating but am guessing I need to increase the amount of coolant in the system because I don't see any when I open in the cap and look in. For a 1950 Cub that gets used only in the summer for mowing (at most a couple hours at a time when its between 65 and 85 degrees) I thought I'd drain it and replace with some new coolant which was question 1:

1. Owners manual says 9 1/2 qts. If I go to the auto parts store and buy some antifreeze and some distilled water, whats the correct proportion to use?

From what I've read about flushing releasing the crud that may be keeping the radiator sealed I'm thinking maybe flushing isn't a great idea right now because I need to use the tractor for mowing the field and can't afford to have a repair project be the result of trying to do the "right" thing.

2. How serious a worry is this? Is there a way of making the flush more "gentle" so it's less likely to cause a disturbance of this sort?

3. And if I just refill so it comes up to the correct level, what mix do I use?

[pickerandsinger]

Well , if it aint broke don't fix it as the old saying goes...You probably won't see any coolant because it will seek its own level and leak excess out the overflow....No water pump, thermosyphonic system I think the word is off the top of my head..I'd add some antifreeze and be done with it...I buy a jug of antifreeze and cut it 50-50 here in upstate NY...Make sure it has the right radiator cap and no one put a pressurized cap on it....Dave

[ntrenn]

Both of mine seek a level that is very deep in the radiator too...and every time i add...it pushes it out the overflow.....
What is important is to refresh the corrosion inhibitors....so i always coach to do makeup coolant at full strength. When its time to refresh...i drain a gallon and put in a gallon at full strength. Plan on a refresh every 3-5 years.
For a complete drain, i always asked the guys to add 1 gallon of full strength, then up to a gallon of water. If vehicle needed more...go 50-50 from there. Very few vehicles will need more than 8 total quarts....
If you always make up at full strength, you will never get low on freeze protection....way more important than boilover....