Inverter and engine coolant change

How many miles Fro?

 

Not sure if Gen III Inverter coolant bleeding is the same as Gen II. But Gen II is super easy.

The engine coolant is a real pain as air gets easily trapped in the Coolant Heat Recovery System thermos. (CHRS).
Real pain to get the air out without tricking on the CHRS thermos pump.

One product I have had excellent results mitigating the aluminum corrosion in the Inverter System is Redline Water Wetter.
Used it in the rad for years and have never had a clogged or corroded rad. It also stopped the aluminum white dust on the cap of the Inverter reservoir:


Red Line Synthetic Oil - WaterWetter® Coolant Additives - WaterWetter®

 

just about 9k more than me. but it isn't just about mileage... time too. did you take a reading on coolant?

fortunately we don't have to worry about the coolant tanks but I imagine the lines leading to the heat exchanger is going to hold a lot of coolant. wonder if there is a drain down there?

 

Changing the coolant is good insurance just to protect the heater core and the radiator, which is basically 3003 aluminum parts.

High PH or caustic solutions are very damaging to aluminum; mild acids; less.

You can use litmus paper to test the coolant. If it turns blue, it past time to change it.

The are no radiator caps as such on the Gen III Prii. Both the inverter and the ICE cooling systems use a resrvoir. So, you'd need either a UView unit or a special funnel with an adapter that fits the neck of the reservoir.

 

Whoa, that seems extreme, even for me.

 

I've reviewed the diagrams of both the ICE and inverter coooling system parts. They are posted here as attachments.

It appears that the complicated "thermos" and related pump system has been eliminated.

The radiator of the ICE circuit is drained with the radiator drain plug on the tank on the back o the radiator on the diver's side. As I recall, the engine cooling drain is on the passenger side of the engine behind the area of the front axle.

I don't know if there is a drain on the inverter houing. If NOT, the circuit can easily be drained by removing one end of the lowest situated hose like on many current GM vehicles without a radiaor petcock.

I own both he Lisle 24610 radiator fill funel;

Lisle 24610 Spill-Free Funnel : Amazon.com : Automotive

and the UView 550000 Airlift system;

UView 550000 Airlift Cooling System Leak Checker and Airlock Purge Tool Kit : Amazon.com : Automotive

I have not tried either on the Gen III Prius but have sed them on other vehicles.

I am hoping that either or both will work.

 

Oh no more thermos on Gen III? Cool...then with a Uview that should be a snap. I tried using my Uview on my Gen II and did not work well at all.

Btw, with its own separate Inverter cooler not body connected to the rad like a Gen II what kind of temps do you see on the Inverter system? I always thought if the cooler was not bolted to the rad (heat soaking it) it would run much cooler making the Inverter much more efficient=better gas mileage.

Thank you for the gif's.

 

You're very welcome.

I looked under the hood of my Prius and found that the components are at four different levels.

The reservoir is at the highest point.

The inverter is below the resevoir, but at a point higher than the pump.

Finally, the cooler is at the lowest point.

I haven't removed the front lower underpanel, but there might be a drain plug on the cooler.

 

If my memory serves me correctly - there's a drain for the inverter coolant somewhere near the transaxle fluid drain. (I believe that the instructions for the DIY transaxle fluid change point it out as a precaution...)

 

Here is some further info... this should be helpful

 

You're welcome. Please let us know how it goes - especially with the air vent in the engine coolant loop and the air purging in the inverter coolant loop.

I have yet to do mine, but I think I'm going to wait a bit (I'm a tiny bit less aggressive than you on the coolant) - but I do want to get my second transaxle change in soon.

Since I see (from the other thread) that you're focused on the value of PM - have you done a brake fluid change yet? I'm going on three years now, and am thinking it's time sometime within the next 12 months...