gulf 1 Posted February 6, 2015 Share Posted February 6, 2015 I have a classic with a K series engine to which I have fitted silicone coolant hoses.After casually talking to a friend at a club night he informs me that OAT RED antifreeze eats silicone hoses/seals.This was news to me,is everyone aware of this.What antifreeze should I be using. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 6, 2015 Member Share Posted February 6, 2015 Comma XStream G30 or equivalent. The last time I looked the cheapest source was Amazon UK.JonathanPS: AFAIK colours aren't consistent across suppliers and products. Link to comment Share on other sites More sharing options...
oldbutnotslow Posted February 6, 2015 Share Posted February 6, 2015 Yup! Link to comment Share on other sites More sharing options...
AntonyH Posted February 6, 2015 Share Posted February 6, 2015 You could also consider the Evans waterless option, but that's not a cheap initial switch due to the cost plus the need to drain and then flush the engine (with a specific flushing fluid as I understand it). Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 6, 2015 Member Share Posted February 6, 2015 And the absence of any evidence of benefit for a K series engine in normal use?Jonathan Link to comment Share on other sites More sharing options...
AntonyH Posted February 6, 2015 Share Posted February 6, 2015 It was a consideration not a recommendation, not knowing how Dave uses his car.It might be a classic with a 200bhp track day screamer for all I know... Link to comment Share on other sites More sharing options...
Dr Slotter Posted February 6, 2015 Share Posted February 6, 2015 Comma XStream G30 or equivalent.Which is a 'red' ethylene glycol based coolant with OAT inhibitors in it. In general, this is what you want for a K-series (and other aluminium alloy engines for that matter). It can damage silicone hoses (it acts as a plasticiser) but would take quite a while. Some silicone hoses come with a lining on the inside which protects them from the OAT. Link to comment Share on other sites More sharing options...
John Vine Posted February 6, 2015 Share Posted February 6, 2015 IIRC, when I first used Comma Xstream (in 2008), it was based on propylene glycol rather than ethylene glycol. Does anyone know why Comma changed? I always understood that PG had several desirable properties compared to EG (notably, much lower toxicity). It can damage silicone hoses (it acts as a plasticiser)I recall a huge stink (2007/08-ish) over the GM product DEX-COOL. It seemed that one of the OAT components, 2-EHA (2-ethylhexanoic acid, or the sodium salt thereof), would degrade/plasticize silicone rubber. Lawsuits were being thrown about like confetti. Presumably the lining that Dr S mentions is designed to counter this?JV Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 6, 2015 Member Share Posted February 6, 2015 IIRC, when I first used Comma Xstream (in 2008), it was based on propylene glycol rather than ethylene glycol.I'm surprised by that: can you remember the type (G30, G48 etc)?It might be a classic with a 200bhp track day screamer for all I know... In which case the benefits of Evans waterless coolant would be... ?Jonathan Link to comment Share on other sites More sharing options...
Mark Durrant Posted February 6, 2015 Share Posted February 6, 2015 ....the benefits of Evans waterless coolant would be...see here Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 6, 2015 Member Share Posted February 6, 2015 :-)I think that's the manufacturer's site: our discussion is here. I'm still totally unconvinced: I just don't think the benefit has been shown in practice for our sorts of engine in our sorts of use. But I'm open to persuasion. I'll go and bounce the other thread.Jonathan Link to comment Share on other sites More sharing options...
AntonyH Posted February 6, 2015 Share Posted February 6, 2015 The bit about working for 20 years rather than needing periodic replacement (Evans quote 1-4 years for water based coolant, don't know if that's in line with what most people actually do / ought to do?) is a pretty positive point, if nothing else. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 6, 2015 Member Share Posted February 6, 2015 Good point. I've put my views in the big thread.Jonathan Link to comment Share on other sites More sharing options...
John Vine Posted February 6, 2015 Share Posted February 6, 2015 I'm surprised by that: can you remember the type (G30, G48 etc)?I'm certain it was a PG-based product, but all I can remember name-wise is that it was called Comma Xstream Red Concentrate. I might even have the old container somewhere but can't check right now as I'm away. But I'm sure it wasn't G30 or G48, for example, as they're later Glysantin-based EG products.In case I was dreaming about the PG bit, I've just emailed Comma (mentioning my 2008 build), and got a response within minutes. They said: We no longer produce a coolant based on propylene glycol, this is because the automotive market generally uses ethylene glycol as it is more easily available and thus cheaper. Propylene glycol is generally used in marine applications as it is more environmentally friendly for the type of surroundings that marine engines are used in.So, it seems I wasn't dreaming after all!PS: Keep pressing for the Evans evidence. I confess to being as sceptical as you (re both the chemistry and the physics, but especially the latter).JV Link to comment Share on other sites More sharing options...
Mechanical Moz Posted February 6, 2015 Share Posted February 6, 2015 The fitting instructions that came with the Classic Silicone Hoses kit I bought a couple of years ago recommended using standard antifreeze due to potential damage from OAT additives. For that reason I went with Comma G48, this was the antifreeze approved by BMW at the time for use in their aluminium engines so I figured it would be fine in my K series. It's cheap enough for me to change it every 3 years instead of the 5 an OAT type might last. Link to comment Share on other sites More sharing options...
John Vine Posted February 7, 2015 Share Posted February 7, 2015 The fitting instructions that came with the Classic Silicone Hoses kit I bought a couple of years ago recommended using standard antifreeze due to potential damage from OAT additives.The CSH website appears to define a "standard antifreeze" as one not containing OAT additives. The implication is that they would prefer you to use one of the older IAT formulations. Do you know whether they recommend a particular brand or formulation? JV Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 7, 2015 Member Share Posted February 7, 2015 ... Propylene glycol is generally used in marine applications as it is more environmentally friendly for the type of surroundings that marine engines are used in. Ethylene glycol is poisonous to humans, and from the mechanism of action I'd expect the same in many animals. So I guess this is about it being dumped and harming wildlife. But I'm surprised there's been a problem in practice because of the dilution.Jonathan Link to comment Share on other sites More sharing options...
gulf 1 Posted February 11, 2015 Author Share Posted February 11, 2015 After a lot of asking around I phoned Comma and spoke to somebody there who seemed to support your theory about using a coolant with no OAT in it.Everyone seems a bit vague about the subject, some suggested that some silicone coolant hoses may have a coating in them to protect them from OAT damage. However as I have no idea whether mine do or not I have chosen to use Comma G48 as you suggest. Thanks for everyones input. Link to comment Share on other sites More sharing options...
John Vine Posted February 12, 2015 Share Posted February 12, 2015 Comma G48Puzzling. According to Comma's site, the MSDS for G48 says that it contains 2-EHA. AFAIK, this is an OAT additive, and is also the one implicated in the GM Dexcool saga mentioned in #8 above.JV Link to comment Share on other sites More sharing options...
gulf 1 Posted February 12, 2015 Author Share Posted February 12, 2015 I am losing the will to live over this issue.Nobody seems to have a definitive answer.I am going to change from Comma G48 to G30 purely because it does not appear to have 2-EHA in it although it does have OAT, and a few people have recommended it.I did see some Triple QX antifreeze in Europarts that did,nt contain OAT but who knows what else it may contain. Link to comment Share on other sites More sharing options...
CharlesElliott Posted February 12, 2015 Share Posted February 12, 2015 I've got silicone hoses and have used red coolant for the last 6 years. (I did use green and preferred using it, but it is difficult to get hold of when you need some in a hurry). No issues at all. Link to comment Share on other sites More sharing options...
John Vine Posted February 12, 2015 Share Posted February 12, 2015 I am losing the will to live over this issueUnderstandable. I'm as confused as you are.FWIW, here's my understanding: The label "OAT additive" covers quite a range of fatty acids and carboxylic acids. 2-EHA is just one example of the latter. 2-EHA also has plasticizer properties, and is believed to have a deleterious effect on silicone rubber. That's what appeared to be the problem in the Dexcool saga. Some silicone hoses come with a protective coating (fluorosilicone) to counteract this. The latest Caterham handbook recommends Millers Alpine Red. The previous edition recommended Comma Xstream Red OAT specifically for CSR and R400. The latter (and maybe the CSR too) comes with silicone hoses as standard. That edition didn't mention G30 specifically. Millers Alpine Red is an EG-based long-life coolant with OAT additives. The MSDS says it contains 2-EHA (sodium salt thereof). The K-series Assembly Guide recommended Comma Xstream Red OAT, but didn't mention G30 either (that product name is relatively new and probably wasn't around at the time that version of the guide was published). Comma G30 contains OAT additives, but the MSDS doesn't say which ones. OAT coolants last a lot longer than IAT ones, and are the coolants of choice for modern aluminium engines. OAT additives have a different physical and chemical action to IAT ones, and take longer to achieve the same level of protection. This can cause problems when components (such as water pumps) are replaced.Of course, I could be off-beam here. If so, perhaps an expert would put me straight?JV Link to comment Share on other sites More sharing options...
Nigel Riches Posted February 13, 2015 Share Posted February 13, 2015 Who make the hoses you have? Why not contact them and ask their advice. Nigel. Link to comment Share on other sites More sharing options...
Simon.Rogers Posted February 13, 2015 Share Posted February 13, 2015 Don't have those issues with Evans Link to comment Share on other sites More sharing options...
John Vine Posted February 13, 2015 Share Posted February 13, 2015 Don't have those issues with EvansBut, surely, that would depend on what inhibitors Evans use? Do you happen to know what their inhibitors are? The only info I can find originates from Evans themselves:"Evans Waterless Coolant is a patented non-toxic liquid comprising of blended heat transfer fluids and a proprietary inhibitor package". One of their FAQs reads: "How do the OAT additives in Evans Waterless Coolant remain in solution without the presence of water?"The answer reads: "Evans Waterless Coolant contains no additive that requires water to dissolve or to enable the additive to function" -- which is evasive to the point of obfuscation. They don't deny outright that they use OAT additives. Their MSDS (for NPG+) merely states: "Proprietary Corrosion Inhibitor Package < 2%"JV Link to comment Share on other sites More sharing options...
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