Is my hydrometer right?

[phenomic]

I have a 97 z28 camaro and I just replaced my water pump. I pretty much got all the fluid out of the car includint the block. Well everything went ok and i filled it with peak lifetime 50/50. I put two gallons because thats all i had and it appeared that i needed just a little bit more fluid to run the car. So i put in half a gallon of distilled water till i got some more. I then bought full strength peak lifetime and added a half gallon of that. So i have a 50/50 mixture.

I bled the system out good and used my hydrometer. Its got 5 balls in it and only 2 are floating. The rest arent floating but they aren't sunk completely to the bottom either. It says if 2 balls are floating only protected to +5 degrees F. I've already went down past 0 and it hasn't froze. I was wondering if my hydrometer is right or wrong and if i am safe for now? Worst temp i think ill have this year is -20 F w/ windchill.

So, should i add some more antifreeze or not? Ive used 50/50 water with dexcool and it floated 4 balls previously but that solution was full of dirt so i dumped it.

 

[labman]

If you haved any of the 50/50 left, or carefully make some and see how many balls flaot. Those things may not be that accurate, but I wouldn't think they would change how they read.

 

[phenomic]

No 50/50 left, I tried to get every last drop out. But i have 2 gallons 50/50 premixed and 1 gallon 50/50 that i made, btw, i did let it do some full heat cycles 3 or 4 times so id think that its probably alright.

Am i safe to leave it in the cold or not?

 

[Chris142]

Unless you pulled the drain plugs on the sides of the block there was still 1-1.5 gallons of water in the cooling systen even with the waterpump removed.

I'd drain out a gallon and dump in a whole gallon of 100% antifreeze.

 

[Matt_S]

I agree with Chris, although I don't think a whole gallon is necessary. I would drain out some and refill with straight antifreeze, though, then see where that gets you. Checking the tester with a known 50/50 solution is a good idea, too. Use a measuring cup to mix it, but wash it VERY well before using it for anything else.

 

[Stinky Peterson]

If you will tell me the system capacity and current concentration I will calculate the exact amount needed.

 

[Big Jim]

Did you test the coolant cold? The tester is not temp compensated.

 

[chas3]

if you didnt flush the block, you can assume the fluid trapped in the block was very likely 50/50 (or "close" enough).

windchill doesnt count for antifreeze. for windchill to be effective you need to have water evaporating (like skin).