Engine coolant – something you may not know

Mike the coolant issue is not well understood and is somewhat more than even you have discovered.

The risk goes well beyond just matching the colour and type. You cannot simply top up a pink coolant into a Toyota for example. Unless it matches the manufacturers specification exactly you run the risk of accellerated corrosion as a matter of course. If you have a look at the Natrad site the provide some good guidance on how to correctly replace coolant.

Hence we always carry a coolant top up supply which has been mixed by our Toyota service department.

At a technical briefing a year or so back we were shown the results of mixing coolants. The prime example was a very nasty and highly corroded WRX cooling system that had only lasted one month after topping up with the incorrect specification coolant.

Given the cooling system is the lifeblood of modern engines and that combined with the chemical reactions of the various metals that go to make up an engine these days skimping on maintaining a cooling system is not something I recommend

RobA

Thanks Mike, I don't venture into the colder regions as you & others do, but it just goes to show how easy you could come unstuck.
I was told years ago that never to assume anything, as the word stood for : it can make an ASS out of U and ME & how true that can be. Cheers.

Hi It is also an unknown that you should within a 2 year period completrly drain and flush both radiator and motor and top up with new coolant to your vehicles specification and I stress the flushing aspect because any residue left in motor or radiator will react with the new coolant.

And it gets even worse. The reason they tell you to flush the system well before adding the new coolant is because in rare instances you will find a brand that is completely non compatable and it reacts with the other brand and impurities and turns to sludge which within days will block your radiator to the point where it will overheat ant the radiator will have to be removed and rodded out and reassembled. Always use the same brand or flush well with the heater tap open.

And use soft water (distilled water) with the glycol mix

Why it pays to consult with the Owner's Manual and use oils, fluids etc that comply with THEIR (stated) standards. Can't go wrong that way.

An interesting read for those of us who think they know everything but don't. (not directed at anyone, just a general statement)

Coolant info

Disregarding any brand names, it's the info that's worth reading.

The solution is simple:
Only use the manufacturer's coolant.

Mixing coolants, even of the same type and specs can result in corrosion and blocked radiators.

So my Toyota vehicles get the correct red Toyota coolant. My Nissan vehicles get the green Nissan Coolant.

And they are both competitively priced.

Hello,
Many moons ago I used to be a member of this site and still come
back to it from time to time as it is probably one of the least "contaminated" sites in the 4wd area.

I read this topic with interest and believe my experience with mixing coolants worth telling.

Background: I have an HZJ 105 (1999 model) and owned since new with 195k on the clock - also - I once was a diesel fitter (term shows my age!).

In a moment of weakness (divorce proceedings etc), I allowed and paid for somebody (who is a good honest mechanic) to service my vehicle. Within 20K of said service, the vehicle experienced; firstly some overheating problems and secondly, the radiator header effectively "blew". When I asked the mechanic what he had put in the radiator as a top up, he admitted that a "no name mentioned here" coolant had been used in a fairly small quantity. To put it simply, green had been mixed with red. I should also add that I had to replace the heater core (which is a s**t of a job on this vehicle).

Anyway, a new radiator later and total (and I mean total!) flush of the system, I now only use the same coolant (red/green whatever
takes your fancy) and change yearly - regardless of what is said on the label.

Hope the helps.

Well now I'll have to read my manual before it goes in for its service (100,000) and if nessacary supply the oils and coolants as set out in the manual.

And make sure it gets flushed completely.

Thanks Mike more for one to remember :).

Brian

read this .
mixing coolants

Yes it's Pandora's Box..! Check out your local Supercheap store , there are around 20 different brands and unless you read the fineprint they all contain Propylene Glycol.! LOL

I also note some make mention to being suitable for diesel engines, others don't.?

With all this in mind can someone recommend a type a or better brand compatible with all diesel engines..?