Radiator + Coolant replacement + bleed procedure?

[Gesta1t]

Howdy folks, I helpfully have the full electronic vw workshop manual - just wanting to know if there are any points to worry about?

Dealer did a new radiator, pump, housing, pipes etc all done 3 years ago - 36,000km later and the radiator has sprung another leak...over 2 years so the dealer doesn't want to know....

The manual specifically notes that you need to both put it in the service position (ie pull the front clip out) as well as use the VAG cooling system charge unit -VAS 6096 (which seems to be a vacuum or pressure fill unit), and talks about accessing and running the "0001 - Fill/bleed cooling system" through the diagnostic tool...

Is all this strictly necessary? Videos on youtube show complete removal of front clip to access radiator, and all talk about just filling and then running the system + massaging pipes....

Any and all tips/tricks/advice/help would be appreciated

[iichel]

filling the cooling system on your EA888 engine is indeed best done with vacuum, like the factory repair manual prescribes.
I have a similar engine in my non-Polo, I just filled it up with coolant and let it run and filled up as all valves opened up. it took several fill-ups to reach the correct level.

a tip could be to take the opportunity to switch to the latest generation of coolant, VW calls this G12 Evo.
viewtopic.php?p=601253#p601253

[RUM4MO]

Oh yes, I certainly agree with "escaping" from G13 and also get rid of any Silicate pouches in the reservoir, if you have one it should have "Mit Silikat" on the reservoir.

I changed my old 2011 Audi S4 to G12evo a few years ago, and bought a DIYer "coolant refill vacuum tool" - which worked very well, I sort of played smart and collected all the old coolant and measured it so that I had a target volume of new coolant that I just had to get back into that cooling system to know that there was not too much trapped air.
Another thing that I now do, before draining any car coolant is, using a cheap coolant system pressure tester, pressurise the system starting with the engine cold and the coolant level mid way between the MAX and MIN, then record the drop in mms when you apply a specific pressure, maybe 15PSI or equivalent, by doing that you will know if you have got rid of trapped air, as air is easy to compress and liquid is not!

My Audi S4 does have an extra electric pump, but it can not get switched using VCDS, hopefully the electric pump in the 6C 1.2TSI can be switched using VCDS to assist in getting rid of trapped air.

I plan on replacing the reservoir with the silicate pouch on my older daughter's 2019 SEAT Leon Cupra which has an EA888 Gen? so hopefully I will be able to find out if that car's electric coolant pump can be switched on via VCDS to assist in getting rid of trapped air when changing it from G13 to G12evo.

[Le_Combattant]

Question about coolant capacity.

I read entirely VW workshop manual and they don't talk about coolant capacity.
Only the fact the capacity may be different due to different setup.

2*5L of G12evo should be enough I think ?

[RUM4MO]

Why that is missing from workshop manuals confuses and annoys me.

I found that my old Audi S4's cooling system capacity, with a manual gearbox, was only 6.8litres, I am guessing - just guessing, that the cooling capacity of my wife's 2015 VW Polo 1.2TSI 110PS with a manual gearbox will be roughly 6litres, so until I hear otherwise I'll am to have 5.5litres of G12evo premixed 50-50 available for when I change the coolant in that car.

A car with DSG would have more than that I'd expect.