How to change Coolant?

[Driftw00d]

I haven't found a definitive How-to on changing the coolant in a 2008 Yaris hatchback.

Many of the ones I've come across were from a couple years ago and most of the replies were "why do you want to change the coolant?". Would someone be willing to help me out and tell me how it needs to be done?

[The Limo 2]

Toyota America says to change the coolant after 100,000 miles then every 50,000 miles after this.
Roy

[bronsin]

Theres a radiator drain on the bottom of the radiator. You turn it with your fingers after taking off the radiator cap (engine COLD!). Theres also a block drain that's very hard to access.

But not to worry. In my ECHO (same engine) ALL the coolant came out through the radiator drain. I never touched the block drain. Some others might back me up on this/say it aint so.

After draining the coolant close the drain and fill the radiator with 50/50 coolant/water (you want distilled water or very clean tap water). Leaving the cap off start the engine and idle it to warm up. At some point the t stat will open and the coolant level go down. Fill the radiator up again and run the engine. The coolant level should be constant at this point. But put the cap on and drive the car around then park it. When the engine is COLD remove the cap and check the level. It should be full. Fill it if it isn't.

Oh yeah you have to drain and refill the expansion tank on the back of the radiator too.

[CTScott]

There are a few threads on here about changing it where I gave the detailed steps. There is a petcock on the back of the engine that must be opened as well to do it correctly. Do a search for "petcock" and you should be able to find the threads.

[Driftw00d]

Thank you Bronsin and CTScott.

[alanwagen]

Forget tap water, well water. Use only distilled water as the others will have calcium which could cause buildup.

[CTScott]

Forget tap water, well water. Use only distilled water as the others will have calcium which could cause buildup.

In a closed system the amount of calcium in water is so minimal (21 mg/l on average) and such a small percentage of that will actually precipitate out of solution, that the build-up from it would be negligible. If it was an open system. where you were pumping many gallon per day of fresh water through it, then you would be concerned about build-up.

[tmontague]

I opened the block petcock when I flushed my coolant last summer and less than 200ml came out so most comes out the rad. I'd recommend doing it this way at Scott said as it ensure a full removal just don't expect much from the block.

I connected a tube to the petcock on the block and used it to guide coolant into drain pan. I left a wrench on the petcock and would just reach back and turn to open or close it when needed. Makes it easier for a quick open/close as finding it and getting a wrench on it every time is a pita.

If you are installing a new t-stat nake sure you have the bleed/jiggler valve at the 12:00 position so the system will automatically bleed itself.

For the week or so after the coolant change check the level and top up as needed. It will take a month or so for the coolant to go back up to the rad cap. For a few weeks after it will sit at the filler neck even if you keep filling it.

To easily empty the overflow reservoir just detach the rubber hose that goes into the filler neck and hold it below the bottom of the reservoir. The fluid will flow out and put a drain pan underneath to catch it. Refill with water and repeat to flush.