Well-Known Forum User
I'm looking at changing the thermostat as I am getting no circulation in the radiator, which remains cold even after some 20 mins of engine running. Think either the radiator is blocked or thermostat not opening.

I'm struggling to track down the green coolant, Nissan tell me they don't have it any more and all I seem to be able to find is either red or blue coolant which I don't thinks is compatible.

Can you tell me what people are using now or where I could get the green fluid from?

Rob Gaskin

Staff member
Site Administrator
Well I would take the opportunity to flush the system and replace the antifreeze with new. You don't need to bother 'matching it up' then.

That's what I did with my 240Z when I got it. The thermostat was knackered but stuck open, isn't that the way they are supposed to fail? Your's appears to be 'blocked'.

Good Luck.


Well-Known Forum User
Thanks for that - called another Nissan dealer to ask what was compatible- they said I need green coolant which they have in stock!!

Think its a case of the parts adviser not being able to find the old part number, rather than actually knowing what it is - just like most of the current mechanics being lost not having somewhere to plug in a computer! None of my local garages even have ability to set timing.



Used Evans in several customer vehicles and one of my own - all good reports, but ensure cooling system in perfect condition before swapping - the leaks are very expensive!!


Club Member
Most tap water contains various minerals (like magnesium and calcium) that form deposits on engine parts. Premixed coolants are (i am told) pre-mixed at factory with distilled water. If any water needs to be added for any reason care should be taken to use only distilled water (not tap or filtered water).


Forum User
Hi guys

I just logged in to ask the very same. I have the thermostat but wanted to see a service guide to doing the change. Any links?
Also, what is this about ‘the green coolant?’ am I going to have to use something specific here for a full change>?



1978 260z in yellow
Club Member
sorry but ive never heard of green coolant so i have to ask what is green coolant? and what makes it different to all the other coolants?
ive had a fair few issues with the cooling in my z at the moment due to old hoses and such so have put in the ordinary blue stuff after replacing lots of parts just in case it leaks again.


Well-Known Forum User
Have a look in the Comma Xstream stable of coolants.

Of course the colour is just a dye used by a manufacturer to indicate what family/type of coolant it belongs to (OAT, HOAT etc, etc). In an ideal world the coolant manufactures should be using the same coloured dye to indicate what family/type it belongs to. But i'm not sure they do.


Club Member
On an old used Z that is 40 years old with original block etc and 100k on the clock I'm sure using distilled water is maybe a bit late in the day now - who knows what has been used down the years.

If I'd rebuilt an engine I'd be going the Evans way ...
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Club Member
I'm using the Evans stuff. Brilliant stuff. Less pressure in the cooling system and no corrosion worries. Had no problems with the engine getting too hot or overheating in heavy traffic. Only downside, if your cooling system is not in good condition it will find weak points and leak plus you need the recommended flushing fluid to remove all traces of water before refilling with the new coolant.


Club Member
I was sent a fantastic article on "Critical Heat Flux within the Nissan L series heads" that I had been holding back for an opportune moment to post it up
Just got to work out where and how to post it on the site


Well-Known Forum User
If you use the water from your tumble dryer,you have distilled water,hence I've never had a problem,so it must be true