Is it straightly drain and fill for both engine and inverter coolants? No flush needed? Back in the days I always flush at least once or twice using distilled water, no necessary on the Prius?
Depends how long the old coolant was in there, and whether you'll be putting a different kind in. If it's being replaced on schedule, or just at the "replace" point on a test strip, and you're using the same kind to replace it, should be fine with no flush.
Thank you, they are due to replace in terms of time (recommended 8 years, now well over for a 2008), but not in terms of cycles (still far from 160,000km or 100,000mi), but yeah they need to be replaced. Watched a couple of YouTube videos, looks quite DIY-able. I ordered a pair of ramps for oil change, still waiting them to be delivered, do you reckon it will be ok to drain both coolants with the car at an angle (raised front)? I can move the car to the driveway where there's a slight decline but still won't be level with the ramps. But would prefer not to work on the driveway because it's uncovered and also in case of spill.
The Australian scheduled maintenance guide sounds like it's different. The 2008 US one is kind of sneaky about the coolant. The charts extend to 120,000 miles and in that whole span they never outright say to replace the coolant. They do, however, say to "inspect" the coolant, and that comes up every 15,000 miles or 18 months. And every time "inspect" the coolant comes up, it is with a footnote number ³. And on every page where "inspect" the coolant comes up with footnote ³, there sure enough is a note at the bottom of the page: ³ Refer to "Engine/Inverter Coolant" in the "Explanation of Maintenance Items" section in the back of this guide for more information. And sure enough, there is such a section at the back, and the first thing it says under "Engine/Inverter Coolant" is to drain and refill it.
So I have watched a few how-to videos, there are inconsistencies. In this video, to bleed the system, he mentioned putting the car into maintenance mode and then to wait for the fan to come on and off twice. In another video from a different channel there's a bleeder valve, and also this video. Are these steps necessary or specific to Gen 2?
On the second video, the guy is partially opening a port on top of the radiator to bleed the engine cooling system - not all Gen2 have that. Otherwise seems to do the business. The third video looks to cover the inverter cooling system. I will flush that system with water to get it clean, then refill with fresh coolant. You have the ignition on or in ready mode and use the metal valve with a hose to bleed. I secure the hose in the tank (as it wants to jump out when there's a bunch of air). It can take 5 minutes or more to get all the air out. Posted via the PriusChat mobile app.
Toyota coolant comes pre-mixed with water, at least in North America. Flushing the system with straight water makes it difficult to subsequently achieve the proper mix. Repair Manual info attached:
