Interesting article on COOLANTS

[haydn callow]

COOLANTS - This is a WARNING to ALL OWNERS
By Stephe Boddice, September 2007 - July 2008
Conclusions within this article are made with the reservation that they are my opinions only, that many
statements relate purely to my own experiences, and that any remedial action taken by owners is at their own
risk. Certain information has been withheld from the article for legal reasons.
In July 2006 I serviced my Phantom III. The engine on this car had been totally rebuild, by me, in
2003 and, following a complete restoration of the rest of the vehicle, it won First Prize in the PIII
class at the RREC National in 2005. The point being that the whole vehicle is in 90+ point condition.
The coolant was two years old and therefore ready for replacement. My local auto spares store, part
of a national (UK) chain, was out of stock of the standard own-brand antifreeze but was fully
stocked with their own-brand 'Advanced Coolant'. The information on the label quoted the usual
compliance numbers, offered extended coolant life, better anti-corrosion protection and stated
that the product was suitable for older engines. On that basis, following a cooling system flush, I
decided to use the new coolant.
After about 4 weeks I noticed damp patches on the floor beneath the engine. Further investigation
revealed that coolant was leeching from almost every possible joint: both radiator top hoses, both
radiator bottom hoses, the Calorstat joint in the header tank, drain tap joint in the bottom tank
plus the weep holes in the block. Tightening joints and hose clips had no effect. My bodily fluids
started to threaten sympathetic reaction with the coolant.
The new coolant was drained off, all hoses were replaced with new items and leaking gaskets
replaced; obviously, the liner 'O' rings were left in situ pending further investigations. The engine
was thoroughly flushed three times and the coolant replaced with a known standard anti-freeze
from a different supplier. The result was that all of the coolant leaks stopped immediately.
Unfortunately, after driving the car, there was evidence that minute amounts of oil had started to
seep from at least three of the weep holes. Bearing in mind that this a concours’ standard car, the
result was not entirely satisfactory.
Cutting a very long story short, I spent 5 months attempting to get the retailers to provide technical
information of any changes made to the formulation of the 'Advanced' coolant compared with their
previous offering. This process went through the usual steps of stonewalling, denial,
acknowledgement of changes, admission of known problems and culminated with them blaming me
for using their product without the manufacturer's recommendation. At this point I escalated the
problem and am now in discussions at Board level within the company, which is, in turn, making the
manufacturer (one of GB's main producers) provide evidence of the product's suitability or
otherwise.
It turns out that the 'Advanced' coolant is manufactured using an Organic Acid Technology (OAT)
corrosion inhibitor pack. The previous anti-freeze used an Inorganic Additive Technology (IAT).
Evidence supplied to the retailer by the manufacturer admits that the OAT inhibited coolant is
known to cause leak problems even in engines that do not use wet liners. The major fault with the
inhibitor being that it attacks, amongst other things, silicone compounds. The most commonly used
base compound for gasket sealants is silicone.
The immediate problem to the buying public is that the manufacturers and retailers are failing to
disclose which inhibitor technology is being incorporated in their coolants/anti-freezes . Anybody
replacing their coolant MUST investigate with the manufacturer which system is employed. It
appears that OAT, and even HOAT (Hybrid OAT), inhibited coolant can be supplied under the same
national compliance standard codes as the earlier IAT technology.
To date, the industry has overlooked the volume/number of old car users who may inadvertently
buy their products and the potential risks that this consumption represents. In 2006 there was a
survey conducted relating to the 'old car' movement and its contribution to the EU economy. In the
UK this was co-ordinated by the Federation of British Historic Vehicle Clubs (FBHVC), which is an
umbrella body, funded by all of the recognised auto clubs, to fight poorly drafted EU automotive
regulations that may accidentally drive old cars off the road. The findings, for the UK alone, were
that this business sector contributed £2 billion (say $3.8 billion) to the UK economy alone. If the
coolant manufacturers and retailers carelessly move to OAT inhibitors without considering the
ramifications on the old car sector they may find that class actions through the courts will damage
their Balance Sheets as much as these products do our old engines.
------------------------------------------------------------------------------------
UPDATE (ORIGINALLY DRAFTED 13TH SEPTEMBER 2007)
Well, folks, this has been a long time coming but the situation has eventually been resolved. For
those who had the patience to follow this saga from its inception I can now give the definitive
answer, which is: -
DO NOT USE OAT INHIBITED COOLANT IN YOUR ENGINE!
I eventually had a meeting with the National Technical Manager of the OAT coolant manufacturer.
He was categoric in his statement that this 'technology' is inappropriate for use in any Rolls-Royce or
Bentley engine other than the latest Bentley GT and Goodwood Phantom. NO 'IFS' and NO 'BUTS'!
Glossary of inhibitor terminology: -
IAT = Inorganic Additive Technology
OAT = Organic Acid Technology
HOAT = Hybrid Organic Acid Technology
The officially recommended coolant for V8 engines is a 50/50 solution of water and ICI 007/400F
antifreeze. The latter is still available from any Official Bentley Main Dealer - see
http://www.bentleymotors.com for contact details.
Changeover history: -
Car manufacturers.
The major car manufacturers were looking for improved coolant performance with, amongst other
needs, extended product life. Engine designs were changed, including new seals, sealants and
gaskets being introduced on a model by model basis. The manufacturers started selectively to
introduce OAT coolants from about 1995 and virtually all engines manufactured since 2005 are now
compliant with this technology.
Coolant manufacturers.
The primary impetus for the coolant manufacturers is to satisfy the needs of their main customers
who are the car manufacturers. The secondary action is to then provide the after-market retailers
with the same products so the market can continue to function. 'Old cars', in the eyes of both are
deemed to be vehicles up to about 12 years old, this being the national average vehicle life in both
the USA and Europe.
No consideration is given to vehicles of a greater age. The decline in the retail sales of IAT coolants
is taken as an indication of falling demand despite the fact that the retailers are encouraged to
promote H/OAT coolant. General ignorance of the product differences has not been considered,
whether this related to the DIY mechanic or non-franchise auto shop operatives. Unless specific
demands are made, by owners of really old cars, IAT coolants will soon be removed from the
marketplace.
Summary: -
The old car movement in Europe has, fortunately, organised a strong lobbying group as a defence
against EU bureaucratic stupidity. The EU legislation drafting machine is constantly putting forward
proposals that would inadvertently remove old cars from the road. Representation has stopped this
by providing accurate data on the contribution that this group of people make to the various
national economies.
When the coolant manufacturer's representative was presented with a copy of the 2005 report he
was astounded, not least by the apparent lost opportunity.
Result: -
1) The coolant manufacturer has undertaken to change its own and its retailers' labelling to
emphasise the unsuitability of OAT in 'old cars'. At the same time it will clarify or reword its
definition of 'old car'.
2) My issue was resolved without recourse the courts, thus depriving the legal profession of a small
income.
3) My car has regained its continence.
4) The coolant manufacturer may actually start to market IAT directly at the owners of those cars
that need it.
YOU HAVE BEEN WARNED!!!

[dandywarhol]

Well found Haydn

I was under the impression that IAT and OAT weren't compatible but flushing out was ok - OBVIOUSLY NOT!

Diesel engines tend to be "wet" liner engines which have rubber seals sealing the cylinder liner from the crankcasings - I can't find any info in the Lushprojects diagrams to prove or disprove that.

Maybe Allan can tell us - he'll have lifted a few heads in his time.....................

[crazy uncle gray g]

Makes you wonder, well spotted Sir

[Tony C]

Well done Hayden,

The following information is available on the Federation of British Historic Vehicle Clubs Website.



Technology moves forward and new products are constantly being launched with claims to improved formulations and performance. With the recent bitterly cold weather in January antifreeze has been in the headlines, with some alarming stories which at first seem to be about the well-known tendency of antifreeze to find the tiniest hole and cause leakages – but in these cases it has led to catastrophic engine problems.

Traditional blue ethylene glycol is a toxic but highly effective antifreeze and contains silicates as an inhibitor to help prevent corrosion in an engine with mixed metals in its make-up. Bluecol and Blue Star are well known brand names and both of these are declared suitable for ‘classic cars’ on their company websites. Be aware that there are also low- or no-silicate ethylene glycol formulations (usually red) available which may not be suitable for all engines.

Propylene glycol is another well-known and less toxic antifreeze formula and usually contains silicates but Comma, the main manufacturer, have now discontinued it in favour of an ethylene glycol product containing ‘bittering agents’ to make it less palatable and minimise the risk of accidental poisoning.

Both of the above products use inorganic additive technology (IAT). Recently problems have been reported concerning the use of antifreeze mixtures using organic acid technology (OAT). OAT was introduced in the mid-1990s and the products are biodegradable, recyclable and do not contain either silicates or phosphates and are designed to be longer lasting. However these products do seem to cause problems in older engines; over and above the ability of antifreeze to find the smallest crevice and leak, OAT antifreezes have been accused of destroying seals and gaskets and causing a great deal of damage in ‘old’ engines. For this reason the manufacturers do not recommend their use in historic vehicles. These products are usually coloured red, pink or orange.

The final category is HOAT. These products use hybrid organic acid technology in an ethylene glycol base with some silicates in the formulation alongside the organic corrosion inhibitors. The product is usually coloured green and are not recommended for use in historic vehicles.

The Federation are still researching this problem but our advice at the moment is:

· only use blue coloured IAT antifreeze in historic vehicles;

· only use OAT products (‘advanced’ or ‘long life’ antifreeze) if the vehicle used it when new and if specifically directed by the vehicle’s manufacturer;

· never mix different types of antifreeze without thoroughly flushing out the system;

· always replace the coolant within the time scale specified by the antifreeze manufacturer as the corrosion inhibitors break down over time.

[haydn callow]

It would seem that OAT coolants do not like Silicone hoses/gaskets/sealant.

Mixing coolants is another subject.

Having recently done a chemical flush on mine and filled with OAT Comma....I will be repeating the process and reverting back to Blucol type.....better safe than sorry.

Thinking about it....Mine is a V6...I winder if the same applies.....I suppose there will be some seals in contact with the coolant.....Mmmmmmmm!!!! ponder

[Diplomat]

I can't be certain without taking it apart, but I wonder if there is a gasket between the metal and plastic parts of the radiator?

Or perhaps I should say "Was"!


Frank

[mikexgough]

Nice article, but I can't for the life of me understand why he would use OAT coolant in a Phantom 111 especially as he rebuilt it..... These cars were built before OAT coolant was even dreamed about

Remember though.....Japanese coolant is OAT based but has little or no silicates in it.....and longlife ....you know the drill....
Interesting comment on the Silicon hoses, I wonder if the Scooby fellas have any issues with their Samco hoses.....mind you they tend to use Subaru super blue ........OE coolant.....

[francophile1947]

Haydn, that is exactly what Bongoben was saying to me at the Summer Camp at Kings Lynn - he wouldn't even touch the long-life OAT stuff with your Bongo

[haydn callow]

Yes...I have had lots of "chats" with Ben and I have always thought that his views are well founded. In fact he will not express a view until he has fully researched it and proved it.

We spent a hour or so chatting about coolants and ...as you say....OAT is a No No !! It was originally developed to go into massive heavy plant to reduce "down time"

[scanner]

but I can't for the life of me understand why he would use OAT coolant in a Phantom 111 especially as he rebuilt it..... These cars were built before OAT coolant was even dreamed about

This explains why..................

The coolant was two years old and therefore ready for replacement. My local auto spares store, part of a national (UK) chain, was out of stock of the standard own-brand antifreeze but was fully stocked with their own-brand 'Advanced Coolant'. The information on the label quoted the usual compliance numbers, offered extended coolant life, better anti-corrosion protection and stated that the product was suitable for older engines. On that basis, following a cooling system flush, I decided to use the new coolant.

[mikexgough]

From BMW forum........

"Do not use silicone hoses!

OEM BMW coolant uses a corrosion inhibitor package known as organic acid technology (OAT). OAT coolants will degrade silicone rubber in a very short amount of time causing the hose to rupture. I've seen it first hand"

[mikexgough]

but I can't for the life of me understand why he would use OAT coolant in a Phantom 111 especially as he rebuilt it..... These cars were built before OAT coolant was even dreamed about

This explains why..................

The coolant was two years old and therefore ready for replacement. My local auto spares store, part of a national (UK) chain, was out of stock of the standard own-brand antifreeze but was fully stocked with their own-brand 'Advanced Coolant'. The information on the label quoted the usual compliance numbers, offered extended coolant life, better anti-corrosion protection and stated that the product was suitable for older engines. On that basis, following a cooling system flush, I decided to use the new coolant.

I saw that Scanner..... But why did he not source his coolant elsewhere....?

[haydn callow]

Because he didn't know as much about coolants then as he does now and after reading the Product infomation on the container it implied that it would do the same job as the "standard" coolant and probably do it better....

[Northern Bongolow]

the plastic rad top and bottom tanks have a (rubber) O ring between the two parts.

[mikexgough]

Because he didn't know as much about coolants then as he does now and after reading the Product infomation on the container it implied that it would do the same job as the "standard" coolant and probably do it better....

I guess so, but having claimed to have rebuilt the engine, surely you would have researched coolants before you use them, I bet he researched the correct lubricants.... Just seems daft to me....especially with a classic car and an investement, oh well takes all sorts