Purple Coolant G13

[rovexCDTi]

I dont really see the point of using it if its only about being 'environmentally friendly', yet costs more and is less effective.

[rich17865]

Originally Posted by rovexCDTi

I dont really see the point of using it if its only about being 'environmentally friendly', yet costs more and is less effective.

It is effective down to -36C, I haven't checked the freezing capability of OAT but I imagine that it is similar.

The OAT is acidic, it burns your skin, and has been know to affect seals and gaskets long term. The G13 is not so harsh and certainly doesn't burn your skin.

[T-Cut]

Originally Posted by rich17865

Posted the image.

Which tells us a lot more than we speculated.
The relevant bit follows Safety Hazards.

What we see is a note that it contains 'more than' 50% ethylene glycol. This is of course the same material used in all conventional antifreeze. What they've actually done is replace around half of the EG with glycerine. I'm not sure whether this is a truly environmental improvement or a simple case of marketing. Toxicity wise there's little difference.

The frost protection is better than a 100% glycerine type. This is because over half of it is ethylene glycol. As I noted earlier, the frost protection from glycerine is only 60% that of EG at a similar concentration. That may be of little relevance in the UK, but these formulas are global products.

The OAT inhibitors are basically salts of certain organic acids like 2-Ethylhexanoic and Sebacic acids. They aren't present as free acid and the antifeeze isn't acidic. If you check the technical data published on OAT systems. you find they have a pH in water of between 7 and 8.5. Inother words neutral to weakly alkaline. The salts of weak acids like those above are weakly alkaline.

The OAT is acidic, it burns your skin, and has been know to affect seals and gaskets long term. The G13 is not so harsh and certainly doesn't burn your skin.

There may be different sensations when 100% EG and 50/50% EG/Glycerine is placed on the skin, but neither will actually damage it (burn). The gasket softening and rubber degeneration is a well understood mechanism and was highlighted in the DexCool debarcle. If you run standard servicing and maintenance regime on the cooling system OAT will not attack anything. However, because the average car owner doesn't always do what they're supposed to do, some manufacturers (Honda for example) have reformulated their OAT system is use sebacic acid salts instead of 2-EHA salts. Sebacic is more heat tolerant than 2-EHA, but less efficient. This necessitated the addition of some of the older style inhibitors like silicate to compensate for the loss of efficiencey.

TC

[rovexCDTi]

As far as i know OAT and this have the same basic additives and its those that cause the seal issues, its got nothing to do with the EG, which has been used in blue anti-freeze for years.

Anti-freeze isnt acidic. This purple stuff is just OAT with glycerine in it instead of EG.

[rich17865]

Originally Posted by rovexCDTi

As far as i know OAT and this have the same basic additives and its those that cause the seal issues, its got nothing to do with the EG, which has been used in blue anti-freeze for years.

Anti-freeze isnt acidic. This purple stuff is just OAT with glycerine in it instead of EG.

The garage I took my car to recommended it over the OAT and they weren't selling it to me. Next time I go I will have to ask them why.

As far as buying it goes, maybe I have been had

[rovexCDTi]

Its the 'latest thing', but it doesnt always make it best. Its just a greener version of OAT, if you care about that use it. Im sticking to OAT.

I think id rather use the Evans coolant stuff before this, although its hugely expensive.

[T-Cut]

Since the purple version contains over 50% of the red version, it's almost certainly a marketing opportunity developed on the current environmental ticket. For all intents and purposes there's no difference between them.

TC