UK / Europe Prius 2 Coolant Change

https://attachments.priuschat.com/attachment-files/2021/06/206709_How_to_Replace_Gen_II_Prius_Engine_Coolant.pdf

 

^That's a very nice document, likely more complete/clear than Toyota's Repair Manual. Anyway, just for a cross-check, I've attached repair manual excerpts (added the inverter instruction, just in case).

 

It sounds like you don't have the coolant heat storage tank in the UK. But you should have a drain on the radiator part of the system not the upper inverter cooling radiator but the lower engine ice radiator push comes to shove just undo the bottom hose coming out the bottom of the radiator assembly that'll drain it pretty much by gravity as it's the lowest point in the system if you're doing all this coolant changing you might be changing a few hoses and then when you put them all back together just take your time and fill it slowly that's about all you can do with the generation two unless you have one of these vacuum filling devices that speeds the process up but reality about it is pouring it in slowly doesn't really take that long you want to put in the recommended volume and that's about it

 

@Lee Tomlinson, follow the instructions in the document linked by PriusCamper but ignore all steps that fuss with the coolant heat recovery tank. The drain and refill is much simpler without it. You may feel like, "Well that was too easy!" because it is. Just remember to check the level at the radiator filler neck every day for a week then maybe once a week for two weeks until you're satisfied all the air is out. For this time you can leave the upper engine cover off.

Best of luck.

 

If you take your multi-tool and you cut off just that little half circle that covers the better portion of the radiator cap you'll be able to remove your cap the rest of the car's life now with that cover in place I never have to move mine anymore You can't even tell that it's been trimmed You can do it with the utility knife carefully and you can't even tell the factory didn't do this now that panel can stay until you have to remove the radiator play with the fans or something I'm just saying if that's appealing to you then you don't have to pop all those little clips up their pictures online I've done it to every car I don't take the panel off to do it I do it while it sits right in place it just takes a second now I can remove the radiator cap on all four cars without pulling any pins or any plastic That's a good thing

 

On our Gen 3 the repair manual instruction says to drain the block, via a spigot on the back/right corner of engine. Hard to get to.

I thought give it a try at least once, even though I’d read lots of comments about it being a waste of time. It was a waste of time: got at most 1/2 a cup for all that effort.

 

Correct.

Yes and yes, on the radiator.

Yes, it is on the inverter roughly opposite the radiator bleed valve. The inverter drain and fill is the same as on US cars and is easy and straightforward.

Correct, not a lot comes out of the engine block drain.

Nope, the thermostat is not a sealed unit and has enough clearance to allow coolant to drain when cool/cold.

 

I drained the coolant, on our Gen 3, with cold engine. For what it’s worth, not sure if it would make a difference.