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The G13 coolant in my wife’s 1.4tsi Blue GT is 7 years old now, and the pH is down to 7, so I want to replace it. I will be using G12 evo. I have never done a coolant change on the EA211 engine before, and I’ve read that it can be troublesome due air locks etc. For this reason I am tempted to try one of the vacuum filling kits which are now widely advertised at relatively low cost. These kits all require an air compressor to generate the necessary vacuum.

2 questions:

Is there really a problem refilling the coolant system on these engines?

How much air is needed to operate a vacuum refill kit? I have a small, very ancient, “Jumbo” air compressor which back in the day I used for paint spraying. It is rated at 4 cfm and 115 psi. Would this be adequate?

Any advice appreciated.

Mike

No idea on whether it is a must to use vacuum refill, but I plan on doing the same.
I think the fact that the water pump is at the top of the head might be calling for that. All cars I've had have had the pump low down on the block and those you just run until the bubbles stop.

I'm down on coolant, below the min mark. Can't see where it's going so I suspect pump gasket leak.
Need to drain coolant anyway to check on the state of the carbon build-up.

The compressor spec seems good enough. The tool is using venturi tube to create the vacuum so I don't think that will have massive air requirement. If you could spray paint then I'll sure it will be adequate.

Is G12 Evo definitely the replacement for G13 these days?
Are you buying the pre-mix of mixing in your own distilled water?

To be honest, you don't really need about tool to vacuum the coolant system.

Here's what I did:

-Empty the coolant expansion tank
-Fill it with G12evo.
-Start engine idle
-Because of engine running, you have to fill the coolant expansion to keep level above minimum
-Wait until water temp reach 90°
-switch on heating system to max temp and wait until color inside the expansion tank is the same as the G12evo.

That's a win.
I'm sure vacuum would work best if you need to drain the system (for example, intake removal).

On a different engine, a 2011 Audi S4 3.0TFSI, I did buy a Draper Coolant Vacuum Refill Kit, and used it with a very very small compressor, and it worked very well.

A couple of maybe smart/cunning things I did when carrying out this task, firstly, connect a coolant leak checking kit to the reservoir and pressurise the coolant system when the coolant is cold, record the drop in coolant when you pressurise it and the pressure used, this can be an easy way to convince yourself that there is no air or no more in the system after changing to G12evo as you can compress trapped air and not coolant, secondly try to collect all the coolant you remove as that will give a guide as to if you have managed to refill with the correct quantity of coolant and so don't have trapped air.

There are possibly other kits available nowadays, but I found the Draper one first, also back when I replaced the coolant in my Audi S4, I could only buy G12evo in 1litre bottles so I had to buy a 10litre container and use that when reloading the G12evo.

I do plan to change the G13 in my wife's August 2015 Polo 1.2TSI to G12evo probably next year when the weather gets warmer, for the same reason as you, ie the ph is heading towards being acidic!

2226/Le_Combattant/RUM4MO

Thank you all for the very helpful advice. I have two cars with the 1.4tsi engine which both need coolant changes in the near future, so I will get the vacuum filling kit since it’s easy to justify the cost and it should minimise any problems. I may also get a pressure tester as suggested byRUM4MO.

In answer to 2226’s question, G12evo is the replacement for G13, which is no longer available from VAG, at least in the UK. It’s only available ready mixed.

Mike

i just found this video

https://www.youtube.com/watch?v=QAcSmQKSfoY


I used autosubtitles to watch it. There is a procedure by the VCDS but i am not sure.


Another one with the whole procedure.

https://www.youtube.com/watch?v=ZfNF0NjbVO8

I just wonder which families of engines, or even which individual engines in VW Group cars, can successfully use that method of replacing the engine coolant?

Edit:- I did not attempt to use a translator when watching these 2 videos.

I checked mine with the help of VCDS, it does not have this ability to vent the coolant.
Engine code CHYB

- With any diagnostic tool:
If a coolant purging/bleeding procedure is not established in the ECU Adaptations, it is because the engine does not need such a procedure.
- With ODIS S:
It tells you if it is necessary and guides you to do it (step by step, easy).

In any case, self-bleeding systems or not, it is necessary to proceed in the correct way (repair manual or knowledge) so that the cooling system is always full of coolant while the engine is running.

Could someone tell me the inner diameter of that pipe ?
I want to buy something to connect in it for the refilling process.





Le_Combattant i hijacked you picture. If there is any problem please tell me to delete it immediately.

Maybe it's 6.3mm (new unused coolant hose). https://www.oemvwshop.com/6c0121447-coo ... e-p313874/


... viewtopic.php?p=598431#p598431

giannis20vt wrote: ↑Sat Dec 16, 2023 1:02 pm Could someone tell me the inner diameter of that pipe ?
I want to buy something to connect in it for the refilling process.





Le_Combattant i hijacked you picture. If there is any problem please tell me to delete it immediately.

I will send you in jail for that !

Ahaha I'm joking man, be free. But IDK why, picture doesn't show up.

ciclo wrote: ↑Sat Dec 16, 2023 6:30 pm Maybe it's 6.3mm (new unused coolant hose). https://www.oemvwshop.com/6c0121447-coo ... e-p313874/


... viewtopic.php?p=598431#p598431

This is the information i want, thanks.
So i need a coupling with 8mm Outer Diameter.