Author Topic: Coolant Silica Bag  (Read 26570 times)

Offline Carbon VW

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Re: Coolant Silica Bag
« Reply #60 on: 29 November 2023, 23:30 »
Recently bought a 2010 GTI PP for my wife. It has the 'Mit Silica' stamped on the reservoir.

Isnt it as easy to take the tank off, puncture the bag to release the crystale, flush them out and then remove empty bag?
i dont think theres such a thing as a Mk 6 2010 PP?
:wink: :wink:

I think you might be correct. I meant a 2019 GTi PP. Just testing,glad you spotted the deliberate mistake! :)
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Offline Adam T7

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Re: Coolant Silica Bag
« Reply #61 on: 30 November 2023, 07:05 »
Recently bought a 2010 GTI PP for my wife. It has the 'Mit Silica' stamped on the reservoir.

Isnt it as easy to take the tank off, puncture the bag to release the crystale, flush them out and then remove empty bag?
i dont think theres such a thing as a Mk 6 2010 PP?

I just bought a new coolant tank, about £30 ISTR. The bag allegedly helps prevent the G13 antifreeze degenerate over time, tested mine the other day and it’s still good enough down to -37. I still siphon the tank out every few months and top up with neat G13 though - a 2 minute job.
« Last Edit: 30 November 2023, 07:08 by Adam T7 »
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Offline Rudedog

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Re: Coolant Silica Bag
« Reply #62 on: 30 November 2023, 07:52 »
I guess you would have to confirm a link between the coolants anti-freeze property (which you can test for) and its continued ability to provide anti-corrosion protection.

Also as others have mentioned the bag was removed by VW late 2019/20 - why was this?

Did they recognise a problem so removed it?

What have they replaced it with if it was needed in the first place - is a coolant change now part of the schedule rather than being sealed for life?

Maybe the newer coolant version has been improved - although I still can't find the Evo version in anything other than a pre-diluted version.

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Offline Adam T7

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Re: Coolant Silica Bag
« Reply #63 on: 30 November 2023, 08:13 »
I guess you would have to confirm a link between the coolants anti-freeze property (which you can test for) and its continued ability to provide anti-corrosion protection.

Also as others have mentioned the bag was removed by VW late 2019/20 - why was this?

Did they recognise a problem so removed it?

What have they replaced it with if it was needed in the first place - is a coolant change now part of the schedule rather than being sealed for life?

Maybe the newer coolant version has been improved - although I still can't find the Evo version in anything other than a pre-diluted version.

G13 has a greater % of Glycerin vs. G12 and it is that which deteriorates, hence periodically siphoning out and topping up with neat G13 to maintain the overall effectiveness.
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Offline Carbon VW

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Re: Coolant Silica Bag
« Reply #64 on: 30 November 2023, 12:14 »
I guess you would have to confirm a link between the coolants anti-freeze property (which you can test for) and its continued ability to provide anti-corrosion protection.

Also as others have mentioned the bag was removed by VW late 2019/20 - why was this?

Did they recognise a problem so removed it?

What have they replaced it with if it was needed in the first place - is a coolant change now part of the schedule rather than being sealed for life?

Maybe the newer coolant version has been improved - although I still can't find the Evo version in anything other than a pre-diluted version.

G13 has a greater % of Glycerin vs. G12 and it is that which deteriorates, hence periodically siphoning out and topping up with neat G13 to maintain the overall effectiveness.
I think you are confused here but im open to be corrected. G12 Evo is newer than G13 and it is the G12 evo that was newly developed to not corrode latest radiator / heat exchanger constructions. My understanding is that you can pretty much put G12++, G13, or G12evo in whatever. Except the latest vehicles that require G12evo; use only G12evo in those.
G13 is Glycerine based and comes as a concentrate you dilute with distilled water (also discontinued I think).
G12evo is confusing also Glycerine based and the latest and greatest. Its basically G13 with additional Phosphate additives (P-Si-OAT). You are not meant to dilute this, hence the higher sale price.
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Offline Adam T7

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Re: Coolant Silica Bag
« Reply #65 on: 30 November 2023, 12:32 »
Not sure about the G12 evo, never heard of it until this thread got resurrected but sounds like it makes sense. I know G13 is still available, I bought some last month.
I guess the bag / no bag debate will continue to pop up but one thing we all have in common on this thread is fact that regular care and attention pays dividends.
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Offline Carbon VW

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Re: Coolant Silica Bag
« Reply #66 on: 30 November 2023, 12:57 »
Not sure about the G12 evo, never heard of it until this thread got resurrected but sounds like it makes sense. I know G13 is still available, I bought some last month.
I guess the bag / no bag debate will continue to pop up but one thing we all have in common on this thread is fact that regular care and attention pays dividends.
Agreed  :nerd:
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Offline breezasib

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Re: Coolant Silica Bag
« Reply #67 on: 22 January 2025, 17:25 »
I got a brand new lease GTI back in the day when they were on a crazy £99 per month deal. Took the train to go and collect it and on the way home the heater would not get warm. Brand new and they wanted to take the dash out! In the end I got them to swap it for another brand new one.

Gives me nightmare thinking about having your dash removed and handing over 1k for the privilege! Finally got around to it:



Offline SuperScaff

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Re: Coolant Silica Bag
« Reply #68 on: 22 January 2025, 18:59 »
I got a brand new lease GTI back in the day when they were on a crazy £99 per month deal. Took the train to go and collect it and on the way home the heater would not get warm. Brand new and they wanted to take the dash out! In the end I got them to swap it for another brand new one.

Gives me nightmare thinking about having your dash removed and handing over 1k for the privilege! Finally got around to it:



Was it easy to remove buddy?

Offline breezasib

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Re: Coolant Silica Bag
« Reply #69 on: 22 January 2025, 22:42 »
Like others have suggested before: I clamped the pipe coming out of the reservoir and then used some needle nosed pliers to manoeuvre the bag out. To be honest it took me longer to actually open the stubborn filler cap than it did to remove the bag.