Contaminated coolant

[kevin48]

Hi all, had my car’s second mot at dealers yesterday. Rec’d advisory re contaminated coolant, suggesting a new header tank, heater matrix & full system clean out. Cost £1211.22p !!!!! Apparently Škoda in their wisdom place a small packet of silica in the header tank to extend the life of the coolant for the life of the car. No mention of this was made by the dealer, just strong advise to have the job done before it became a major issue. I can see and feel the “bag” in the tank. To the touch it it feels to be full of a gravelly substance. I intend to remove this after first removing the header tank & flushing the entire system. Usual dealer warnings- very difficult, expensive chemicals required etc. All you need is a vacuum pump and a bit of dexterity to remove the hoses etc. I believe this was common across the whole VW group,although my sister’s mk5 golf,purchased the same week as my car,april2016 is marked On the tank has having the substance in, it cannot be seen. Both cars were brand new factory order and have similar mileage under 30k. 
has anyone on here come across the same problem please?
Kevin. 

[bigjohn]

Er just a few:-

and...

 

Edited 8 August, 2020 by bigjohn

[boydeee]

Yes. They've had these blooming silica bags in their tanks across the VAG group for a good few years now. I'm not overly convinced myself and would rather it wasn't fitted after seeing how many components need replaced 'if' the bag fails.

 

After seeing the Octavia owners linked by @bigjohn, I think I'd be keen to swap mine out as I was hoping to hang onto this car until it's well out of warranty.

[bigjohn]

I'm lucky wih my 1.4tsi 2014 Superb - they don't seem to fit the dreaded "Sillykat " bag with the smaller petrol tsi engines. My sons 1.2tsi 2016 Octavia III doesn't have it either - Indeed it was something we looked for when buying last year!

 

There is a replacement header tank available without it and surprise surprise the dealers usually even have these in stock. It was fitted to slowly replenish silica in the g13 coolant. To compensate adding a G13 coolant refresh to the service schedule every few years would suffice(good idea anyway!) - I think it's to do with minimising corrosion of aluminium components within the engine.

Edited 9 August, 2020 by bigjohn