EV System Coolant Change

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Bloggsy

Well-known member
Joined
Sep 10, 2019
Messages
67
Hi folks - so I've managed to change my EV system coolant and wanted to share this knowledge so others could do it and save the garage fees! ;)

Some are probably aware that there are 2 cooling systems - 1 for the EV and 1 for the ICE. The ICE part is located to the front right (as you face the car engine bay), and the EV is located to the left, with the reservoir above the radiator).

I've not looked at the ICE coolant, yet, so may have a look when I get the chance!

So, for the EV coolant I put the car onto a small set of ramps so I could get underneath and remove the underbody cover (there are 2 covers - the large one covering the whole engine comes off first. It's held on by 2 x 10mm bolts and some plastic clips. Then, there is a smaller cover, underneath the radiator and front of the engine which is held on by 2 more 10mm bolts and even more plastic clips!).

This gives you access to the small plastic screw on the bottom left of the radiator (I think they call this a 'petcock'), but turning it drains the fluid from the radiator - initially, it comes out from a small pipe behind this screw or you can keep turning the screw and the screw will come out and the fluid will come out from where the screw was!

You obviously have to remove the EV coolant reservoir cap first (make sure the coolant is cold / cool and then unscrew the top, and remove it), then unscrew the petcock (catching the fluid in a suitable container). Once the fluid stops flowing out, screw the petcock back in and tighten by hand back to its original position.

Looking at the EV coolant reservoir, you'll see 2 pipes coming out of it, to the left - 1 at the bottom and 1 just above the 'minimum' level mark. Using pliers, I removed the 'clamping' clip and pulled off the hose (I think it has an internal diameter of 15mm) and connected another hose to it which I directed into an empty container.

Next, I prepared my coolant (I used Prestone coolant which mixes with any coolant, so shouldn't cause any blockages). I think you'll need around 2.5 litres as I had 3 litres and had a little left over as well as some water, if you want to flush the cooling system.

Then, fill the reservoir with water to just under where the top hose (i.e. the hose you've just removed) comes into the reservoir - you'll know if you've overfilled as water will spill out! :lol:

With your charging cable disconnected, press the 'Start' button twice (without pressing the brake pedal) and immediately press the 'Eco Mode' button at least 10 times within 7 seconds. This will start the water pump and it will go off and on, circulating the coolant.

Head back to the engine and top up the reservoir to just over the 'minimum level' (again, if you try and fill it up more, it will spill out the side where you've disconnected the hose). At first, the reservoir will drop quite dramatically as it will fill up the radiator, but should settle down a bit after that - I would suggest having about 5 - 10 litres of water ready (depending on how much 'flushing' you want to do).

When the coolant coming out is clear, you're now flushing the system and at any point, you can go back into your car and switch it off. This will also stop the water pump.

Turn the petcock and empty the radiator of water, before you screw the petcock back in again and re-fit the hose to the reservoir, then fill the reservoir with coolant to the top of the reservoir. There's still water in the system, so you could fill up the reservoir with concentrated coolant and allow it to mix with the water, if you want.

As before, press 'Start' twice without pressing the brake pedal and top up the reservoir with coolant, keeping it at the 'maximum' level, until the level doesn't drop anymore and then, switch off the car.

To bleed the EV coolant system, press 'Start' twice with the brake pedal pressed and immediately press 'Eco Mode' at least 10 times within 7 seconds and let the water pump circulate the coolant for 1 - 2 minutes, topping back up to the 'maximum' level mark when needed.

Finally, switch off the car and re-screw the reservoir cap back on - done! :D It took me just under an hour.

Hope this helps!

Cheers

Bloggsy
 
The coolant in the EV system is ultra long life coolant and components inside your system may not be compatible with the coolant you have used.

Seems a bit early to be doing a coolant change, Why the need?
 
DibbyDibbyDJ said:
The coolant in the EV system is ultra long life coolant and components inside your system may not be compatible with the coolant you have used.

Seems a bit early to be doing a coolant change, Why the need?

Hi DibbyDibbyDJ - I read that it was 'guaranteed' for 5 years and it should be (and it was) a 'simple' job. I had just replaced my brake discs, pads and fluid, after it had a service, as well as the front and rear transfer case oil so thought I'd get this all done whilst I had the chance.

I'd read on some of the other forums that other owners had used Prestone as it was 'universal' and mixes with any coolant and is compatible with our Outlander.

Cheers

Bloggsy
 
Here is Australia, even with its harsh conditions, the EV coolant is 20 years lifespan.

I would not trust any other coolant in the EV system other than the genuine blue. It is more expensive, but worth the peace of mind. As for water, this should also never be added to the EV coolant mix.
 
DibbyDibbyDJ said:
Here is Australia, even with its harsh conditions, the EV coolant is 20 years lifespan.

I would not trust any other coolant in the EV system other than the genuine blue. It is more expensive, but worth the peace of mind. As for water, this should also never be added to the EV coolant mix.

Yeah - I always use distilled water. Sorry, probably should have highlighted that! :oops:

20 years? :eek: Well, I suppose I don't have to worry about the ICE coolant for a while :lol:

Cheers

Bloggsy
 
Bloggsy said:
DibbyDibbyDJ said:
Here is Australia, even with its harsh conditions, the EV coolant is 20 years lifespan.

I would not trust any other coolant in the EV system other than the genuine blue. It is more expensive, but worth the peace of mind. As for water, this should also never be added to the EV coolant mix.

Yeah - I always use distilled water. Sorry, probably should have highlighted that! :oops:

20 years? :eek: Well, I suppose I don't have to worry about the ICE coolant for a while :lol:

Cheers

Bloggsy

ICE coolant 10 years here. Same coolant, just different job.
 
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