From what I read about mixing coolant types you would be better off running river water in your cooling system.
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From what I read about mixing coolant types you would be better off running river water in your cooling system.
I did some research on coolants for Series land Rovers.
http://www.aulro.com/afvb/series-lan...r-engines.html
There is OAT, HOAT and good old ethylene glycol (IAT or CAT)
The colour only tells you what dye they use, not the formulation.
Early OAT coolants caused a lot of problems for older engines so they now have a 'type 2' OAT which overcomes the problems (allegedly).
Major advantage of OAT/HOAT seems to be the extended life. But as stated, if changing from OAT/HOAT to IAT then a good flush is the best recommendation.
Colin
OAT and HOAT's are still 96+% ethylene or propylene glycol, it's the anti-corrosion package that's different ;)
The OAT Land Rover used (Texaco) was the first of it's type and used a compound known as 2EHA which unfortunately acts as a softener on some elastomer's used as seals which creates leaks.
It also capillaries out a lot more easily than a conventional silicate based coolant and it doesn't appear to like air in the system at all.
OAT's have much better heat transfer than silicate based coolants, but everything has to be absolutely schmick in the cooling system or you'll create headaches for yourself.
I've had good luck with it in a few vehicles but JC and Pat have much wider experience and subsequently hate it with a vengeance, and FWIW I've gone to a HOAT (Cummins-Fleetguard) to minimise any potential problems ;)
And the CAT OAT is the same as Land Rover OAT with a small addition of...bugger, can't recall, but it's almost identical, they are both made by Texaco :(
Interesting Cummins have made the wholesale change to a propylene glycol HOAT, sounds like they've had problems too.