Thread: Coolants for older engines

Appreciate the info and look forward to further discussion/consensus on this. It's something I have wondered about.

Valvoline don't have an IAT coolant in Australia, they have a HOAT that "can be run in some older engines" problem is whether the Landy is one of the "older engines" they refer to.

Nulon list a 2 year shelf-life for Dr Cool. They are not saying it won't work but it's difficult for them to give a "guaranteed performance" after that date. I wonder how they would prove it's manufacture date if you had a problem after a year. I don't keep the empty bottle or the receipt (but maybe I should). I've asked whether there is a date code on the container, I await the reply.

Awaiting a reply from Castrol still.

Any other coolant suppliers I should try ?


Colin

I use the standard green tectaloy coolant available from kmart, supercheap most servos, repco, autobahn and truck stops everywhere.

Originally Posted by Blknight.aus

I use the standard green tectaloy coolant available from kmart, supercheap most servos, repco, autobahn and truck stops everywhere.

The thing is does it use IAT, OAT, HOAT or some other corrosion pack.

I've just emailed Tectalloy and also Shell so more info as I get responses.


Colin

Castrol Anti-Freeze Anti-Boil is HAT (Hybrid Additive Technology) . I mentioned to them that I'd been using this in my old vehicles and the reply was that "if I had been operating trouble free then I should continue to use the same product".
I might send another enquiry from another email address asking for their recommendation for a 50+ year old vehicle.

Shell replied but recommended an OAT or a long life (no details of the corrosion pack) so I've gone back to them for further information because I'm not keen on using OAT and specifically asked for IAT.

Just been browsing the net again :-
Tectalloy Extra Cool needs to be replaced every year.
Tectalloy Extra Cool Gold lists only a Km replacement (60,000 if tap water used and 100,000 if demineralised water used). It's a second generation OAT.

As a 'rule of thumb' it seems that if the coolant needs replacing every 2 years or less then it's probably IAT or maybe HAT.
Ethylene Glycol raises the boiling point and lowers the freezing point of the coolant but may not be needed if it's not originally specified. Apparently it helps deal with local hot spots within the engine where the temperature may get above 100C. A corrosion inhibitor added to distilled/demineralised/soft water may be OK for Series Land Rovers.

The more I look into this the more confusing it gets, especially when the 'Technical Support' for the companies don't give straightforward answers.
It's going to end up like a discussion on oils where everyone has their own preference because of what they believe.....


Colin

Interesting reply from Shell who state that their OAT & HAT coolants are OK for older vehicles

"Yes, Shell do sell coolants suitable for older vehicles.
We assume that IAT is inorganic additive technology, more commonly known as CAT - conventional additive technology.
Our product, HD Coolant N Pre-Diluted, is such a product.
I have attached a TDS for your information.
However, our HAT (hybrid additive technology) and OAT (organic additive technology) products are also suitable for older vehicles.
In the distant past, incorrectly formulated HAT and OAT products could sometimes cause seal and solder issues.
Our Shell products, LongLife OAT (OAT), MultiVehicle Antifreeze Coolant (HAT) and HD Premium N Antifreeze Coolant (HAT) have never shown any issues with solder and seals.
Hope this helps."

It seems that the OAT, HOAT (HAT) problems were in the past and most coolants should now be compatible.

Being a creature of habit it looks like I'll be staying with the Castrol Anti-Freeze Anti-Boil and put up with the 2 year replacement. Autobarn have 20% off for RACV members this month so I'd better stock up.

Hope this helps.


Colin

Now I'm confused .....

Tectalloy replied
" You are correct an in-organic / conventional style coolant is much better suited to older vehicles.
We have three products in the Tectaloy range that meet this criteria.

Tectaloy 60 Plus is a pre-mixed ready to use conventional style coolant. Formulated for general purpose use and is designed to meet the demands of normal passenger vehicles under light to normal driving conditions.

Tectaloy 90 Plus is a pre-mixed, 33% anti-freeze anti-boil ready to use conventional style. Suitable for passenger vehicles requiring anti-freeze anti-boil protection, and those vehicles put under increased loads e.g. towing

Tectaloy Anti-Freeze Anti-Boil is a conventional style concentrate, that can be blended between 25% - 50%. Suitable for passenger vehicles requiring anti-freeze anti-boil protection, and those vehicles put under increased loads e.g. towing "



Different answers from different companies.


Colin

You dont need antifreeze here in Aus unless you are going to park your car in alpine areas for more than 1 night. Antifreeze, ethylene glycol, is sugar based, and will turn corrosive in the wrong concentrate. It also crystalizes over time, depositing an insulating layer iside your radiator. A 5% loss of flow caused by this layer can cause your cooling efficency by around 20%!
All you need is a good quality corrosion inhibitor. We use the Tectalloy OAT coolant at work and have never had a problem.