How much coolant to add?

[Tims65]

I have been running straight water in my cooling system in my new engine until I made sure I had a good sealed system. I'm now flushing the water to get a good clean flow, then I'm going to add coolant/anti-freeze. My question is how much coolant should I add to get a consistant 50/50 mix coolant/water? How much water is held in the block?

Thanks,
Tim

 

[Midlife]

It all depends upon the size of the radiator you have. Total capacity is typically 2.5 gallons.

 

[johnpro]

I'd dump 1/2 gallon of anti-freeze in there. That should get the remaining mix to pretty close to 50/50. Then fill anti-freeze bottle back up with distilled water, and dump that in. Then just continue using the empty anti-freeze container to keep mixing 50/50 coolant and filling the system the remainder of the way with it.

 

[Tims65]

All right, I flushed out the cooling system until I had clean water, then drained out the radiator and filled it with 1.25 gallons of anti-freeze/coolant. I then topped it off with a little water, so I should be good.

Thanks,
Tim

 

[cmayna]

Tim,
I like 80% distilled water, 20% coolant and a bottle of water wetter. Ever since I went to this recipe, my temps have stayed very consistant at 180+ degrees.

 

[sigtauenus]

All right, I flushed out the cooling system until I had clean water, then drained out the radiator and filled it with 1.25 gallons of anti-freeze/coolant. I then topped it off with a little water, so I should be good.

Thanks,
Tim

There is a $5 tool at the auto parts store that measures the coolant percentage. It works like a turkey baster, you suck up a bit of coolant from the radiator, then a little floating needle points to the percentage of coolant vs water.

 

[KBMWRS]

It really depends on your locale and the usage of your car. Winter...freezing temps?
Around here I use the same mix as Craig noted since we just have to fight off the rare below freezing temp and basically use the coolant as lubrication along with the WaterWetter.