Hi don't know if this has been asked before so here goes my coolant expansion tank looks a little crappy inside although there's no bits or sediment inside i don't know the cars history the coolant still pink but I've noticed when engine is cold and when i top up the coolant lid is a pig to unscrew and a pig to tighten until it clicks I'm wondering if it's worth changing the tank for a new one i haven't used much coolant maybe 400ml over 11 months I know they're not the best pics

Get a new one.

This says Mit Silikat on the side and so it has a silica bag inside, which is designed to aid the life of the coolant, but eventually breaks down and blocks the cooling system.

Whilst you don’t want it to be urgent, if the header tank looks like it’s had a fair innings and your cooling system is working ok (I think you notice a lack of hot air when things go wrong) then I’d say you’re possibly getting towards being on borrowed time on this.

Thanks and what's the part number for this i've seen so many but don't want cheap nasty or second hand tanks i want original new parts and probably get the system flushed

1 hour ago, travs said:

Get a new one.

I would agree, only because it looks like you can't get access to the silica bag to remove it from your existing tank. New tanks are relatively cheap ~ £35.00 ish.

1 hour ago, Chris40 said:

coolant lid is a pig to unscrew and a pig to tighten until it clicks

Mine too, but I think that's part of the design.

I would like to change mine do Skoda do a genuine part without the bag and if so anyone know the number ?

Yes they do but I don't know the number. Lots of Briskodans have upgraded to eliminate the bag.

Result 30 seconds and a couple of smelly coolant fingers later ! 😄

in my previous 2016. Mk3 i have preventively replaced 5Q0 121 407 G to 5Q0 121 407 M

~ 30 euros

-> https://www.briskoda.net/forums/topic/490705-silikat-bag-in-coolant-resorvoir-diesel-engines/?do=findComment&comment=5515679

-> https://www.briskoda.net/forums/topic/475223-expansion-bottle-replacement/page/8/#comment-5435158

 

At least that design of coolant reservoir has a cap that you can use a convenient sized bit of metal in (the slot), to help open it, I tend to wash the cap and that clears most of the solidified dried coolant off it and so it becomes a bit easier to open and close.

Newer models of cars tend to have the later version of caps which are quite tricky to remove - in fact the tool supply industry has responded by providing "sockets" that fit the various sizes and shapes, I think that VW Group ended up using caps that have an odd number of flats on them, which is a bit challenging for people that use a set of pipe grips to help them open them! Ford, I seem to remember, chose an even number of flats on their later cars.

Why has this become a difficult job, okay in an ideal world you should never need to top up coolant - but when you feel the need to, provoked probably by VW Group crappy plastic pump/thermostat assemblies, then life becomes annoying struggling with these later designs of coolant reservoir caps.

2 hours ago, Nick_H said:

Result 30 seconds and a couple of smelly coolant fingers later ! 😄

I used long tweezers, the end result was the same but without the smelly digits.😁

I changed mine about two years ago I think. I didn’t buy an OE one, but a dirt cheap one from eBay.

I decided to keep the G13 coolant in place and added a VW silikat cartridge, which is far more substantial than the teabag used in the OE tank. Also, the cap is dead easy to open and close and it hasn’t had any ill effects on the performance.

Edited 21 August, 202521 Aug by numskull

17 minutes ago, Gammyleg said:

I used long tweezers, the end result was the same but without the smelly digits.😁

Haha I kind of enjoyed the smelly fingers …

Part number changed in sept 2024 to 5Q0121407AA and genuine can now be obtained for just over £20

AKS tuning

Genuine VAG Coolant Expansion Tank - No Silicone Packet!...

The coolant expansion tank in your vehicle allows additional fluid a place to go after expansion

3 hours ago, s88urd said:

Part number changed in sept 2024 to 5Q0121407AA and genuine can now be obtained for just over £20

AKS tuning

Genuine VAG Coolant Expansion Tank - No Silicone Packet!...

The coolant expansion tank in your vehicle allows additional fluid a place to go after expansion

Thanks 😁

5 minutes ago, Chris40 said:

Thanks 😁

BTW part number works at VW, Skoda, Audi and Seat.

So if you have a VAG dealer closer than your local Skoda dealer they should still be able to help.

I replaced mine a couple of weeks ago. In stock at my local dealer, and just under 20 quid:

SKODA Parts Direct

Genuine SKODA Parts Delivered To Your Door

Genuine SKODA Parts at discounted prices

Hope that helps,

Nick