Went to dealership for coolant change and they filled it with water - Page 2 - Toyota Yaris Forums

tmontague · 03-05-2015, 01:20 PM

I use the block drain and rad drain and very little actually came out of the block. I'll likely not bother with the block drain agin since I'll be changing every few years.

I use deionized water and will not use tap water. I've seen too much build up on my home humidifier within a month to even think about putting that in my cooling system.

When flushing the system I found that it was easier to just remove the thermostat and let the engine run. I did this when it was cool outside and I didn't feel like waiting for the fan to kick on as it was taking too long. If you run it with the thermostat removed it will cycle instantly. Just don't do this too long as it will leak quite a bit with the thermostat removed so make sure you keep adding water every few mins.

This seemed to clean everything out really well and then I just added Toyota Red coolant that I mixed with 35-40% water (winters get stupid cold here) and it is looking extremely clean since. I noticed that the coolant level slowly lowers more during the winter than the summer usually every 10,000km I'll add a couple ml's.

As a side not, the coolant wasn't right up to the rad cap after I changed it, after about 2 months of driving it finally normalized and went back up to the cap. I am not sure if this was air in the system but I did install the new thermostat correctly with the air purge hole in the 12:00 position.

03-05-2015, 01:20 PM	#19
tmontague View User's Garage Drives: '08 2zr swapped Vios M/T Join Date: Oct 2012 Location: Caledonia Ont. Posts: 2,938	I use the block drain and rad drain and very little actually came out of the block. I'll likely not bother with the block drain agin since I'll be changing every few years. I use deionized water and will not use tap water. I've seen too much build up on my home humidifier within a month to even think about putting that in my cooling system. When flushing the system I found that it was easier to just remove the thermostat and let the engine run. I did this when it was cool outside and I didn't feel like waiting for the fan to kick on as it was taking too long. If you run it with the thermostat removed it will cycle instantly. Just don't do this too long as it will leak quite a bit with the thermostat removed so make sure you keep adding water every few mins. This seemed to clean everything out really well and then I just added Toyota Red coolant that I mixed with 35-40% water (winters get stupid cold here) and it is looking extremely clean since. I noticed that the coolant level slowly lowers more during the winter than the summer usually every 10,000km I'll add a couple ml's. As a side not, the coolant wasn't right up to the rad cap after I changed it, after about 2 months of driving it finally normalized and went back up to the cap. I am not sure if this was air in the system but I did install the new thermostat correctly with the air purge hole in the 12:00 position.