Can the radiator & invertor be flushed & refilled without purging the air ? I read several threads where some of them have refilled without using vaccum to purge the air out. I think the proper way is to using a vaccum device to suck all the air out of the system before filling with new fliud. this insures proper heating & cooling. Any thoughts?
you can't flush in the traditional sense, just drain and fill. ABSOLUTELY NO VACUUM on the inverter, unless you want to replace it. that's what makes it so tricky. DH never used a vacuum tool on the engine coolant either out of precaution.
In some of the tech-training seminars I was helping out with they were using an AirLift on the inverter circuit, at least on a Classic. Why not on the inverter loop, does it pull on the hoses too hard and let the barbs cut into them from inside? . _H*
the inverter runs at something like 5psi, putting vaccum on that would crush it like a coke can. the vacuum tool DH has (and i'd presume most standard vacuum tools but he's not here to tell me that) are made for ~15psi systems.
In another forum somewhere around PC, it was suggested that you just short the relay that runs the coolant pump to get the air out. I will state as that person did that I don't warranty this solution though. I don't remember the name of that thread but I'm sure you can find it. I did however short the relay with a paper clip when I drained my inverter coolant. No ill effects when I did it and it did get a lot of air out.
This is a previously discussed issue, and one with conflicting opinions. These guys seem to have no problems using a vacuum tool: Art's Automotive - 30K Service, 2nd Generation Prius Maybe they have researched the max vacuum to apply and have some way of limiting their application of same. Guess you just have to make the call for your own vehicle.
Regarding the inverter coolant change, there's no need to short any relay terminals, as the coolant pump will run whenever the car is READY. The 2G inverter coolant loop is relatively easy to purge air out of (compared to Classic), and I see no need to use a vacuum tool. Regarding the engine coolant change, I previously had suggested shorting the CHS relay terminals at brief intervals to force the CHS pump to run and fill the CHS canister. Galaxee expressed concern about whether this would cause a problem with the valve that controls fluid flow to the canister. Therefore if you decide to use this approach, caution is required.
The OP claims to have an '07 Prius. There is absolutely no need whatsoever to touch the cooling system that soon on a vehicle run on organic acid coolant technology.
i asked a tech about changing coolant on a prius he tells me due to the cast aluminum design of the engine that somehow keeps the coolant very clean, also using toyota SUPER LONG LASTING COOLANT only makes that combo a better one. And to even add the icing on the cake the engine barely has a hard life! having the electric motors doing most of the grunt work for us! I'd be more worried about the battery than the engine at this point, engine is living the good life when it comes to the prius.
I helped a local owner with 80K miles change coolant. The drained coolant was nice & clean, if poured into a punchbowl you would have no hesitation to drink it.
Even though the coolant is clean I'd be interested to know how the differnt additives in it hold up. Like the water pump lubricant ect. I was alwyas under the impression that that's a big reason to change the coolant. I regular car, when the coolant gets flushed and goes thru that machine, I was always under the impression that the machine readded the proper additives. I guess we can't do that with the Prius though, correct?
Thanks for the feedback. I talked to the local dealer, they use it for convenience but it is not mandatory.
