Should this be something I should do?
Have you done it? Yes or no and why?
Sent from my CLT-L09 using Tapatalk
Have you done it? Yes or no and why?
Sent from my CLT-L09 using Tapatalk
Removing silicone bag from coolant?
- Thread starter Oliver Pawley
- Start date
My car had the Mit Silkat marked on the reservoir when I picked up my 280 back in July 2014, and after various problems related to the bag started appearing in this forum, I checked my coolant bottle. There was no bag in mine (dealership removed it?) and since then I have suffered no problems, so I would say just remove it, and then it can't burst and cause the blocked radiator problems.
Just done a quick Google to see what the purpose of the silica bag is:
"The coolant expansion tank contains a silicate repository. Silicate is used to protect the aluminum components in the coolant
system from corrosion. There are silicates in the G13 coolant, but they are used up over time if the engine is subject to high
thermal loads.
To compensate for the silicate consumption, silicate is taken from the repository and added to the coolant. The silicate
repository provides additional protection against corrosion for the aluminum components in the coolant system over the entire
lifespan of the engine."
Not sure if changing the coolant is somewhere on the service schedule, but it sounds like the silica bag makes the coolant last the lifetime of the car. If the bag has been taken out, you must have to plan in periodic coolant changes to keep the aluminium protection up.
"The coolant expansion tank contains a silicate repository. Silicate is used to protect the aluminum components in the coolant
system from corrosion. There are silicates in the G13 coolant, but they are used up over time if the engine is subject to high
thermal loads.
To compensate for the silicate consumption, silicate is taken from the repository and added to the coolant. The silicate
repository provides additional protection against corrosion for the aluminum components in the coolant system over the entire
lifespan of the engine."
Not sure if changing the coolant is somewhere on the service schedule, but it sounds like the silica bag makes the coolant last the lifetime of the car. If the bag has been taken out, you must have to plan in periodic coolant changes to keep the aluminium protection up.
Maybe not in this forum, or this section of this forum, but I'm sure that someone has reported that G13 has "gone" from dealership parts lists, it is all G12evo now, okay so maybe this is due to a change to a "less polluting to manufacture" base compound/solution - I've seen that mentioned before, but does this change to G12evo make the "mit silikat" redundant - and anyway, as I've said in the past, the service life of the base compound/solution must be what limits the period any coolant is fit for continued use in these systems - and the source of most of these compounds/solutions only gives them 5 or so years, so why did VW Group give the impression that the coolant, or at the original fill of engine coolant was "for life"?
Way back when I ran Fords, Ford also indicated that their own brand of engine coolant was "for life" - maybe all a bit confusing, okay it is possible to ignore that and flush and replace the engine coolant at a sensible point in the car's life, just maybe a nuisance bleeding the system properly with some engines.
Way back when I ran Fords, Ford also indicated that their own brand of engine coolant was "for life" - maybe all a bit confusing, okay it is possible to ignore that and flush and replace the engine coolant at a sensible point in the car's life, just maybe a nuisance bleeding the system properly with some engines.
After the manufacturer warranty expired on my Leon, I have started taking it to VAG specialist instead of Seat for servicing. On the first service they had it in for, they removed the bag from my coolant bottle and explained the potential problems it can cause (bag splits, blocks heater matrix, expensive repairs etc).
The coolant can't be "for life" as suggested above - when the cambelt/water pump is changed at 5 years or 140k miles, the cooling system is drained.
Removing the silica bag was one of the first jobs I did on my Leon. Done following all that I read about the bags bursting and clogging heater matrix
Removing the silica bag was one of the first jobs I did on my Leon. Done following all that I read about the bags bursting and clogging heater matrix
The trouble is, there is no real need to just drop the old coolant out, in any case it needs to be collected and disposed of in the correct way (what ever that is), so could be reloaded into the coolant system if it was collected as carefully as this nasty stuff should be.
My other issue is, if the car has a chain drive for the camshaft, then there would not be any regular need to remove the coolant.
Worse than that, some of the newer engines that have a camshaft drive belt, and that belt only requires to be replaced if or when it shows signs of wear, have the water pump at the other end of the engine, so the coolant system might not even need to get opened up to replace the cambelt.
I'd rather play safe and replace the coolant at some point in time, but VW Group does not, so far, give that service point in respect of G12++ or G13 - at least not that I've spotted and I have the official workshop manual for a 2011 B8 S4, and 2015 6C Polo and a 2019 Leon Cupra.
Edit:- is there any connection with fitting a Silcate bag and the actaul version of VW Group coolant loaded in at the factory, or is it related to or connected to the version of engine fitted? It is still as clear as mud for me.
Another Edit:- what I'm trying to do by jumping into some of these threads related to coolant versions and/or Silicate bags, is to try to end up with a clear and correctly informed understanding of "what" and "why" so that this info can end up as a resource for others in the future - nothing more or less.
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