Coolant Question

bertieduff · Post by **bertieduff** » Tue Sep 19, 2006 4:34 pm

Fitting an uprated radiator from those very helpful peeps at Eliseparts...thing is, Havoline XLC OAT coolant, the orange factory fitted stuff....where the flip can you get this? Google, local motor factors and halfrauds are all giving me blank looks. Any suggestions or wots a good alternative?
Does orange tango do just as well?

roadboy · Post by **roadboy** » Tue Sep 19, 2006 7:03 pm

You just need any OAT anti-freeze. Most motor factors stock it. Just ask for the pink/red/orange stuff. Rather than the blue/green stuff.

HTH

Dan@JPS

Sanjøy · Post by **Sanjøy** » Wed Sep 20, 2006 9:56 am

Or wait for the halfrauds sale

bertieduff · Post by **bertieduff** » Wed Sep 20, 2006 2:29 pm

cheers guys...btw what's the difference between the orange and the blue/green stuff?

Sanjøy · Post by **Sanjøy** » Wed Sep 20, 2006 2:39 pm

OAT is the Orange / REd stuff. Cannot mix the two and system needs flushed prior to changing.

robin · Post by **robin** » Wed Sep 20, 2006 5:38 pm

Sanjoy wrote:OAT is the Orange / REd stuff. Cannot mix the two and system needs flushed prior to changing.

Actually, you can mix the two. The primary difference between OAT and normal Ethylene Glycol type of coolants is the length of time that they provide protection against corrosion (they both provide similar freeze/boil points and heat carrying capacity). OAT is designed to last up to 5 years if kept in perfect condition and there are no leaks in your engine. After that it will run out of the alkaline content required to prevent electrolysis taking place (at which point you start to lose aluminium).

OAT (and EG) coolants are destroyed by mixing with air or exhaust gasses, so head gasket and/or expansion tank failures will reduce lifetime (hence the 5 year life is a moot point for Elise owners

).

If you put an EG coolant into an engine currently filled with OAT you will reduce the lifetime of the coolant to (conservatively) the expected lifetime of the EG coolant - 1-2 years.

If your car is in warranty you must fill with specified coolant, obviously.

Cheers,
Robin

roadboy · Post by **roadboy** » Wed Sep 20, 2006 6:00 pm

robin wrote:
Sanjoy wrote:OAT is the Orange / REd stuff. Cannot mix the two and system needs flushed prior to changing.
Actually, you can mix the two.

Apart from the fact that they quite often produce a thick sludge when mixed, greatly reducing the efficiency of the already weak cooling system on the Elise.

What Sanjoy said is correct. A full system flush is recommended.

Dan@JPS

robin · Post by **robin** » Wed Sep 20, 2006 8:37 pm

roadboy wrote:
Apart from the fact that they quite often produce a thick sludge when mixed, greatly reducing the efficiency of the already weak cooling system on the Elise.

What Sanjoy said is correct. A full system flush is recommended.

Dan@JPS

To quote Dr. Paul Fritz, senior coolants technologist for ChevronTexaco Products Co., "Nothing bad will happen" when two brand-name coolants with different corrosion inhibitor technologies are mixed. By this he means that no sludge will form, there will be no damaging chemical reactions and the coolant will still carry heat and protect against freezing.

For all the claims that mixing the coolants causes sludge to form there are a similar number of claims that it is mixing OAT with air that causes the sludge. Now you wouldn't need to top up the coolant if you didn't have a leak (normally) and a leak means air ... so perhaps the sludge was there without the topping up.

But the thing we can certainly agree on is that if you want to protect your engine and cooling system against corrosion, flushing and replacing the coolant every couple of years is a good idea. I would bet that if you filled the car with a mixture of brand new OAT+EG coolants you wouldn't have any more problems than if you filled it with just one or the other.

Rover used both OAT and EG in the same engine, so I don't think either of them are incompatible with the engine and given that they don't react with one another it should be fine.

But each person should do what they think is best for their engine.

Cheers,
Robin