The great OAT hunt.

[mick160]

Originally Posted by neilb740

I usually have to top it up every couple of months (sooner if ive done a lot of miles) and its rarely more than about 250ml, so its not exactly gushing out. Its been like that since ive had it.

I have been planning to do a coolant flush as its not had one for 4 years that i know of.
So are there no ill effects to swapping to blue?

No, it just needs changing more often.

It has been mooted that oat causes degradation of silicone seals/gaskets.

[MG Tom]

Originally Posted by mick160

No, it just needs changing more often.

It has been mooted that oat causes degradation of silicone seals/gaskets.

Note it is 2-EHA present in some OAT coolants that does this. Use OAT without 2-EHA (such as Comma G30) and you'll be fine.

[DMGRS]

I'm going back to blue, I've not had a single 2 year period where at least one cooling system component hasn't failed, causing me to lose it all anyway.

[SD1too]

Originally Posted by MG Tom

Comma G30 is red OAT ... I emailed Comma and they confirmed it doesn't have 2-EHA, which is the thing that caused all the issues with GM and Dexcool and degrading silicone etc.

Well that seems to be a favourable conclusion to a long standing forum discussion: OAT vs. blue antifreeze. Thanks Tom.

Simon

[crofts]

So are we saying the Vauxhall OAT that many of us have been buying contains EHA and is therefore unwise to use.
I seem to remember discussion on here that running with a strength of about 30% instead of 50% overcomes the problem of seals etc deteriorating and will protect way lower than the winter temperatures we experience here in U.K.

[SD1too]

Originally Posted by crofts

So are we saying the Vauxhall OAT that many of us have been buying contains EHA and is therefore unwise to use.

No David. No claims have been made about Vauxhall OAT one way or the other. All Tom has said is that Comma has informed him that their G30 product does not contain 2-EHA.

I seem to remember ... that running with a strength of about 30% instead of 50% overcomes the problem of seals etc deteriorating ...

A member said that he was experimenting with a lower concentration, but nothing has been proved.

Simon

[Dorset Bob]

Originally Posted by crofts

................... I seem to remember discussion on here that running with a strength of about 30% instead of 50% overcomes the problem of seals etc deteriorating and will protect way lower than the winter temperatures we experience here in U.K.

I have seen that too.
However, it is not just about protection from freezing. The corrosion inhibitors are formulated to give optimum protection at a 50% mix.
The OAT attack on seals is a theory anyway, and I would not want to compromise the protection of the engine itself, for the sake of this.

50% mix for me.

[T-Cut]

The bulk of the car maufacturing worldwide industry uses an OAT based antifreeze as standard fit. It's decades since the problem with EHA was recognised and reformulation to less controversial inhibitors has been going on all the time. EHA has been replaced with sebacate and other organic salts to eliminate the issues that started the Dexcool debarcle. And remember, the issue was underpinned by a history of cooling system neglect by the plaintiffs. Whatever, can you imagine that the Dexcool you can buy today from any Vauxhall outlet is the same stuff? Even the very latest purple antifreeze (so-called environmentally/ecologically friendly/non-toxic and fitted as standard by Volkswagen and others) is an OAT system. The unfortunate thing is very few OAT bottles tell you what's actually inside. If anyone's nervous about that, switch to a green/blue or whatever colour you prefer. The thing is, there's dubious stuff about those you don't know about either.

As for buying OAT, I reckon Euro Car Parts does the best deals and free delivery. The way to find it is search for 'red antifreeze'.

Euro OAT: http://www.eurocarparts.com/red-anti-freeze

TC

[berkshirelad]

I'm not allowed to use the yellow anti-freeze any more