coolant question

[suppjc]

Hi guys,

a few weeks back, I found out my frs had coolant very low in the reservoir tank (I think it's called over flow reservoir?). Back then I added distilled water (~0.5L, definitely less than a liter) in the overflow reservoir.

Now the winter has come, it may fall -30C or under during the season, which hasn't happened yet. The previous owner kept the car parked outside all the time, so the coolant itself seems fine. Anyways, I was worried that adding distilled water would dilute the coolant, but as far as I looked up, if there was any liquid that has evaporated, 'only' water would have been but the actual coolant would have remained, so adding distilled water wouldn't hurt?

I thought of checking out the coolant itself with the squeeze up bottle thingy with a dial in the middle (the thing that tells you the freezing point lol don't know the proper name for it), but I'm not sure where I can stick the tube and suck up the coolant in the first place.


I wonder what you guys think.


Thanks.

[gen3v8]

Get it out of the overflow bottle and put it back afterwards if you`re not sure

[soundman98]

get a bottle of super blue to keep on hand, toss some in to the right fill line, and go with it.

https://smile.amazon.com/Genuine-Sub...7877850&sr=8-1

the water is going to evaporate over time from hot/cold cycles, as it's not an entirely closed system, so just keep it topped up, and it'll be fine.

[Ultramaroon]

Squeeze bottle coolant tester thingy is a good tool. If you check it from the radiator cap, make sure the check valve on the cap is nice and clean before you reinstall it. 99.5% of the "I'm slowly losing coolant" issues are due to a leaky check valve.

After a few heat cycles, fluid in the reservoir is pretty much the same as what's in the system.

[Sapphireho]

Just drive it, you'll be fine.

And like soundman said, if it goes low again, top off with proper antifreeze.

[soundman98]

i used to buy the non-diluted stuff so i didn't need to pay for half-water, but after realizing my captain-n-cokes that ought to be around 50/50 are really about 90/10, i figured i'm not enough of a mixologist to do a proper job, so i ought to let someone else handle the mixture!

[FR-S2GT86]

Hydrometer.

[SCFD]

It'll usually take a few heat cycles for whatever is in the coolant overflow to mix with the rest of the system. Considering that you put in distilled water a few weeks ago, I'm assuming it's been enough time to not worry about it.

However, since you have a hydrometer on hand, just stick it into the overflow tank and take a reading.

[suppjc]

Thanks for the feedback people.

Maybe what I wrote earlier wasn't so detailed. I put in distilled water like 2 months ago, so no doubt that it's been all mixed up with the rest of coolant. Albeit small amount (~0.5L), my main concern was the increase in the freezing point of the coolant since I'm living in Alberta, Canada where it drops below -30C from time to time, which hasn't happened yet thankfully.

I don't have a hydrometer with me yet but will buy it at the end of the week and see if I can pull out some of the coolant to test out.

IN CASE I HAPPENED TO FIND THE FREEZING POINT IS HIGHER THAN WHAT I WANT, is there a third party undiluted antifreeze that I can mix to lower the freezing point? From everything I read from this forum and other websites, they all recommend the OEM coolant, which is right, but it protects as low as -37C, which seems like a borderline to me..


Again, thanks for the comments people!

[gen3v8]

If you see near -40 I have no Idea I know a higher concentration of coolant lowers the freezing point but reduces the systems efficiency. Scary to be honest

[new2subaru]

Originally Posted by suppjc

Thanks for the feedback people.

Maybe what I wrote earlier wasn't so detailed. I put in distilled water like 2 months ago, so no doubt that it's been all mixed up with the rest of coolant. Albeit small amount (~0.5L), my main concern was the increase in the freezing point of the coolant since I'm living in Alberta, Canada where it drops below -30C from time to time, which hasn't happened yet thankfully.

I don't have a hydrometer with me yet but will buy it at the end of the week and see if I can pull out some of the coolant to test out.

IN CASE I HAPPENED TO FIND THE FREEZING POINT IS HIGHER THAN WHAT I WANT, is there a third party undiluted antifreeze that I can mix to lower the freezing point? From everything I read from this forum and other websites, they all recommend the OEM coolant, which is right, but it protects as low as -37C, which seems like a borderline to me..


Again, thanks for the comments people!

In you case I would go to the dealership and get a flush and fill. It's cheap and can't hurt. I've lived in AB and -40C is no joke. You must use a block heater, no?

[suppjc]

Yup, I have a block heater. On the other hand, I might be just overthinking, considering I've been ok with other cars in the past. I'll try the hydrometer to see how the antifreeze is in the coolant and see if I need to flush, which I doubt I need to because it's still a low mileage car (~60000km). I looked up the coolant exchange process, and it seems doable. I'll see how it goes.

Thanks.

[Ernest72]

Originally Posted by suppjc

Yup, I have a block heater. On the other hand, I might be just overthinking, considering I've been ok with other cars in the past. I'll try the hydrometer to see how the antifreeze is in the coolant and see if I need to flush, which I doubt I need to because it's still a low mileage car (~60000km). I looked up the coolant exchange process, and it seems doable. I'll see how it goes.

Thanks.

The 50/50 blue says it’s good to -62F. So you diluted it a bit. Maybe to be safe, just do your own refresh. No flush, just replace fluid in reservoir and drain radiator and replace with new 50/50 blue. All said maybe 1hr of work in your drive way. Make sure you burp the system (run the car with the heat on, until the fans come on), using a coolant overflow attachment. This will remove all the air from the system.

[new2subaru]

Most anyone is capable of doing a flush. Most wouldn't want to do it at -20C