[sujak]

Originally Posted by JD_STI

6.5 Quarts (6.15 Liters) came out. That includes what came from the reservoir tank, which was at the full mark. I'd say about the same amount of new coolant (including the conditioner bottle) went back into the system. That would leave about 1.5 Quarts that never came out. That just seems like a lot of old fluid to leave in there. I'm thinking about changing it again since I never opened a whole gallon of the coolant.

But when routinely changed every 30k It isn't. Most of any fluid you change there will always be a remainder, You could have flushed out the system with water too, but not worth it. I also think doing another coolant change is useless.

STi takes 8.1quarts of coolant. When i did my change we probably drained 6 to 7 quarts like yourself and filled it up with what was taken out. No problems . Coolant will be changed at 60k again.



*Side Note*

When doing my coolant change we didn't have to remove the reservoir to drain it, it drained along with the radiator. Could it just have been the thermostat was open allowing for coolant to drain back into the radiator as the radiator was being drained.

[flytojungho]

hey, I was told that it's a good idea to flush your radiator before filling it up with coolant with distilled water (fill the system up with only distilled water and let the car warm up to flush). Also, I heard that to burp the coolant after the fill, you can just start the car with the radiator cap off and let the engine heat up, and burp the system. I believe that this will save people some time.

Anyone else tried these methods?

[theGraySTiG]

flushing that way shouldn't hurt anything, but if your coolant looks fairly clean when you drain it, there should be no need. that seems like a lot of extra work. i actually bought enough distilled water to do that, but when i got to the point of refilling everything later in the day, and was burping it, i decided to just set the water aside for my IC spray.

[RufusAZ]

I want to to do my coolant this weekend but mix in some Water Wetter. Does anyone know what ratio I should use of water, coolant and water wetter for a daily driver and once a month track day?

[theGraySTiG]

if you never see any freezing temps in your area, i'd reconsider whether to use any anti-freeze. just water, wetter, and conditioner may be enough for you. in AZ, you certainly don't need a 50/50 mix. i don't know the ratio of wetter to use, but i'd hope they'd have the answer on the bottle.

[RufusAZ]

They have suggestions on the bottle. It can drop into the 30's at night during the winter in Phoenix. Nothing too cold though.

[Mykl]

Originally Posted by STI Sibb

Hi Rennes,

Your coolant system holds about 7.7 liters. It is recommended that you put 1/2 distilled water (3.85 liters) and 1/2 undiluted coolant (3.85 liters) into the coolant system.

The undiluted coolant bottle you bought is 3.75 liters and is 100% coolant without any distilled water mixed in. You need to find a way to mix it with 3.75 liters of distilled water and then pour the mixture into your coolant system.

I recommend buying a 50/50 premixed solution bottle in addition to the undiluted coolant you bought. Your Subaru dealership should have both on hand. If you have the 50/50 premixed solution, you can pour it in first. Then you will have an empty coolant bottle to pour half of the 100% undiluted coolant into. You can check that the bottles are at half by holding them side by side in the light or looking down through the cap. Once you have the levels equal, fill both bottles near to the top with distilled water. Put the cap back in place and shake. You now have 2 more bottles of 50/50 premixed solution.

Does this help? Someone else might have another suggestion on how to do this.

Why not use two bottles of 50/50? I guess I don't see the point in adding any undiluted coolant to it if you can buy it premixed. Because you're running greater than 50% coolant. Too much coolant can be hard on your water pump since it doesn't flow as easily as water.

Given that I live in Alabama and don't really need anywhere near that much pure coolant I would probably throw in an entire bottle of 50/50 premixed and top it off with plain distilled water instead of undiluted coolant.

[theGraySTiG]

Originally Posted by Mykl

Why not use two bottles of 50/50? I guess I don't see the point in adding any undiluted coolant to it if you can buy it premixed. Because you're running greater than 50% coolant. Too much coolant can be hard on your water pump since it doesn't flow as easily as water.

Given that I live in Alabama and don't really need anywhere near that much pure coolant I would probably throw in an entire bottle of 50/50 premixed and top it off with plain distilled water instead of undiluted coolant.

read it again. he is diluting the full concentration stuff to 50/50. the reason for buying the undiluted and mixing it yourself is to save money, albeit not much.

[Mykl]

Originally Posted by theGraySTiG

read it again. he is diluting the full concentration stuff to 50/50. the reason for buying the undiluted and mixing it yourself is to save money, albeit not much.

Reading comprehension > me

[a14ypzz]

is it better to flush out the coolant system with water or w/e before doing this?