Antifreeze, Silicon hoses and 'classic' engines

[techbod]

Recently I bought some silicon hoses - when I picked the up the vendor advised that I should make sure I didn't use an antifreeze that contained any organic anticorrosives (OATS/HOATS etc), since they could damage the silicon hoses.

After further reading around the subject, it turns out there is a strong body of evidence that many of the anti corrosion inhibitors used in modern antifreeze formulations can cause serious issues when used in 'classic' engines. There is a typical writeup here: http://www.rrbew.co.uk/Pdfs/Derek%20Har ... 9%20V8.pdf. The FBHVC has also covered this as have many other classic car owners (google is your friend)

Also as a cat owner, Ethylene based antifreeze is horrendous stuff to have around.

Eventually via google I found this lot: http://aaasolutions.easywebstore.co.uk/ ... tions.aspx
which is the only UK based source for 5 litres I could find. Its a bit of an odd site, but I bit the bullet and ordered from them. The antifreeze and flush duly arrived and is about to go into the 7 . Only time will tell if its any good.

Even if you don't want propylene it might be worth looking at your the back of your antifreeze to make sure its ITA, not OATS. I notice that Halfords advanced antifreeze states it is suitable for use in older vehicles but contains OATS - so I would argue it isn't suitable for use in older vehicles.

All IMHO of course and I guess you already knew all of this...

[sgrant]

I've bought some of this stuff and I'll be shoving it in over the weekend.

[erictharg]

I wouldn't use any of the new orange coloured long life coolant additive in an old engine. Stick with something that is glycol based - usually blue in colour. For max heat rejection forget anti freeze and add some "water wetter" (redline do one). Anti freeze reduces the capacity for water to transfer heat, so straight water is better for cooling. The water wetter breaks down surface tension and increases things again, from a performance perspective. Just ensure you drain the system come winter!

[erictharg]

OK. So, now I have read the article, and whilst Ethylene Glycol is not the nicest stuff on earth to drink, just like many substances in this world we managed to use it for decades without too any children or cats drinking it. So don't get too worried. Propylene Glycol sounds better if you can get it. I@ll be running plain water with some wetter added this year as I need all the "coolth" I can get!

[techbod]

> Stick with something that is glycol based - usually blue in colour

That's problem - they are all glycol based but with different additive packs and colour is no longer an indication of what has been added. I checked in Halfords - they offer two different antifreezes , both blue, both Ethylene gycol. One has an ITA pack, the other is OATS. If the FBHV are correct one will destroy your silicone hoses, turn your engine into dust, sell your house and ruin your credit rating. (A little over the top but you get the idea). The other is OK. Both blue.

> we managed to use it for decades without too any children or cats drinking it.

No, unfortunately it is an issue. In the US, approx 1400 children are poisoned each year from Ethylene Glycol ingestion and a larger number of cats and dogs. http://www.humanesociety.org/news/press ... 21709.html - Assuming the stats are correct does seem like a very high amount of children and presumably that doesn't mean they all/any die.

I assume as normal (obesity etc) we follow the US and have a suitably scaled issue.

We definitely seem to specialise in Nutters wishing to harm pets also use it deliberately.
http://www.dailymail.co.uk/news/article ... adius.html
http://www.dailymail.co.uk/news/article ... rries.html
http://thescotsman.scotsman.com/scotlan ... 6713569.jp
http://news.bbc.co.uk/1/hi/scotland/nor ... 078780.stm
http://www.eveningnews24.co.uk/news/nor ... g_1_770158
(apologies for using the daily mail )

Comma now add a bittering agent to at least one of their Ethylene Glycol antifreezes, which is a good start. If I remember correctly France has some legislation in place on Ethylene Gycol and I hope Europe follows suit, or at least mandates the use of a bittering agent. I won't be holding my breath though

> Propylene Glycol sounds better if you can get it.

Well I'll let you know now I have some- if I ever find the key for my crank pulley, so I can put it back on and start the engine that is...

[erictharg]

You've got me Marcus! Your facts beat my pub bluster and I stand corrected. I'm even going to check the "blue" stuff I bought last year for mine out of curiosity. I'm no great lover of cats, or most Americans come to that, but I don't wish them any harm. I'll even pick up that saucer of anti freeze I usually leave in the garage...

[sgrant]

I shoved in the stuff that Marcus linked to above, over the weekend. The procedure is to drain and flush everything, fill up with a "flushing agent", run the car for an hour, then flush it all out and fill up with the premixed coolant.
The flushing agent looks very, very, very suspiciously like it's just a small quantity of the coolant! It's all a very strange luminous green/yellow colour, rather like some screenwashes. Anyway. It's in. Hopefully it won't do anything nasty to the engine...

stephen

[techbod]

The flushing agent is an alkaline mixture which I assume is designed to scavenge out all that rust and scale that you might have floating around in there. I do wonder what happens if your cooling system is being held together by rust and the sludge is keeping the leaks at bay - but I'll find out when I do mine...

Edit for an update.

Just been through the same procedure with the same flush and antifreeze. In the interests of science and proving they aren't the same thing (despite I admit being very similar in colour), I found my Johnsons Indicator paper and measured both. The flush went a very nice shade of purple which was as alkaline as my paper will measure - ph 11. The antifreeze was greenish came out at approx ph 7.