[wojfreestyle2002]

does anyone know any links to a write up on how to flush the coolant the correct way on a wrx/sti. i heard you can use a hose and water to make sure all the old coolant is drained. not exactly sure of the correct way to do this so that you dont have any air in the lines afterwards, which would lead to the engine running real hot real fast

thanks

[spazegun2213]

1) drain coolant
2) fill back up with water (or new coolant mix)
------------------------ if you are doing a complete flush do 3 and 4
3) let car run and come to operating temp
4) repeat 1-2
-----------------------------------
5) let car come to operating temp, and open coolant bleeder valve (now i have no idea where this is but i would assume its close to the radiator and as high on the system as possible.
6) close valve once coolant starts to come out
7) have a beer.


I've done flushes on several cars and they are all the done about the same way.

[Del]

Originally Posted by spazegun2213

1) drain coolant
2) fill back up with water (or new coolant mix)
------------------------ if you are doing a complete flush do 3 and 4
3) let car run and come to operating temp
4) repeat 1-2
-----------------------------------
5) let car come to operating temp, and open coolant bleeder valve (now i have no idea where this is but i would assume its close to the radiator and as high on the system as possible.
6) close valve once coolant starts to come out
7) have a beer.


I've done flushes on several cars and they are all the done about the same way.

It seems like our radiator cap is located on the highest part of the cooling system, therefor any air in the system should make its way to the cap. Just park on a level surface and let the car run for maybe 10-15 minutes.

[blueman05]

so if im doing a complete flush i want to drain the radiator then fill with water and run it with water for 10 min or so then drain water and refill with coolant? is the prestone 50/50 mix ok to use? also im a little confused on the coolant bleeder valve and burping the system???? someone please explain better.... pics help greatly....

kevin

[rek888v2]

Like the guy above said, its easy, Ive done it twice. I did it the hillbilly way though. I pulled off the lower radiator hose, drained the system, ran the hose through the radiator and Turbo revisour (or however you spell it) until I saw all the crap and such stop comming out. I put the hose back on, refilled the system, ran the car with the Turbo revisour off (being the highest poiunt in the coolant system, and as it burped and sucked in coolant, I kept filling her until she overflowed. I capped her up, went for a drive, drank my self silly that night then after she cooled off, I checked her levels and called it night.

[elirentz]

There's no need to do a full "flush" unless you've seriously lapsed on your service (you're supposed to do it every 30k miles. The way I do it at work (subie dealership) is drain the coolant, at the bottom right of the radiator, and then refill with subaru coolant. I use only subaru coolant and the subaru additive in mine because subaru designs their coolant and the additive to help with head gasket leaks.

[blueman05]

subaru coolant and disstilled water? 50/50 mix? plus the additive?

[elirentz]

Yeah 50/50 mix plus the additive would be best. Destilled water would work too but at work we just use tap water with no real problems yet.

[blueman05]

now i was at the dealership today and they said when flushing the system to remove the thermostat or it could get damaged???

[elirentz]

If you are trying to flush the entire coolant system with pressure maybe. I wouldn't worry about it if I were you. Have you been faithful with your services so far? Is your coolant really dirty like really really dirty? What makes you want to flush it so bad? A drain and refill is all you really need unless you have serious sludge in there. If thats the case you really need to just flush your radiator.

[blueman05]

coolant is bad i have 26,000 mi on the car but i had my radiator hoses done and when the refilled it back up i dont know what they used for coolant i know they didnt use subaru stuff.... i just wanted to get the right stuff and mix in there with the additive to make sure... found the drain **** on the radiator looks like a ***** to drain cause theres that metal plate going across.... probably better off draining from lower radiator hose? i was gonna drain it out and remove the thermostat and then use a garden hose from at the radiator and then the tank by the turbo and flush water through it then refeill with 50/50 coolant mix and additive.... would this be ok?

[elirentz]

Yeah that won't hurt anything. Draining from the butterfly valve can get messy it doesn't usually come just out the little spout and usually travels down that subframe rail. If you remove the lower radiator hose you don't need to worry about the thermostat because that is what it is attached to on the engine side. IMO at garden hose pressure it shouldn't harm it anyway.

[blueman05]

but wouldnt the thermostat block the water flow flushing the block?

[oce420]

lol i need to do this too, can someone make an official DIW thread? Thanks

[blueman05]

that would be very helpful.....