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MG MGF Technical - Coolant Top-Up

(Apologies if this is a re-run of previous thread(s))

I hope this isn't a portent of a developing problem.......

Having had my TF160 for 11 months, I finally read the handbook section on coolant level, as I suspected that mine wasn't p'raps as high as it should've been. Well, it wasn't by quite a lot and I need to top it up. Hopefully (wishful thinking) it was underfilled at the factory??!!

Anyway, the question is, I seem to remember someone writing here that they had trouble obtaining the "correct" type of coolant (with OAT corrosion inhibitors, whatever THEY are).....what was the outcome?? What do I need to get and from where??
SimonKE

Don't, just use water, the tiny amount you are adding to the system will not dilute the concentration to any perceptable degree.
Will Munns

IIRC from the previous thread a week or two back, it you're just topping up you don't need to put any extra coolant. Plian water shoulf be fine and it won't affect the coolant:water ratio by hardly anything.

I'm sure someone will either back me up or correct me!
Billy Bob

Must type quicker!
Billy Bob

How low is the coolant? Normally I just use ordinary tap water for the minimal top up that my *F* has required.

But if it requires a large volume then it is perhaps best to take it to your dealer and get them to top it up and check it out - after all the car is still only 11 months old and must be due its first annual service soon.

Ted
Ted Newman

>But if it requires a large volume
Remember that the collant system for the F is in excess of five litres, and that is diluted by hand to 50/50, so there is much scope for errors in both directions, adding even a few pints would be fine.
Will Munns

You can obtain OAT from your local MGR dealer. I think that all new F/TF use the stuff, it was only the older cars which used Super Plus 3.

This coolant is mixed 50/50 with water, preferably distilled. The coolant system takes about 5.25 litres so if only a little topping up is required then distilled water from the kettle (avoid those nasty bits at the bottom) will be OK and will just dilute the mixture a little. A correct mix of coolant will only freeze at about -38 degrees or something so a little more dilute will not really effect this too much, and the corrosion resistance should still be fine.

However if filling is more like a litre then is may be prudent to have the correct mix.

When filling make sure you only fill to the correct level, Maximum half way up the expansion tank. Only do this when the engine is stone cold!

It may be that the coolant has dropped as a result of airlocks being released, However, the system is a closed one and no topping up should be necessary so monitor things and if the coolant still drops take it back to MGR to find the source of teh leak.

HTH

Tim
tim woolcott

Blimey, guys, that was quick!!!

The coolant level this morning after a 15 mile drive was about a third of the distance from the bottom of the tank to the relevant seam....so quite low but, assuming the quantity of coolant required is the volume to the seam (i.e. the level doesn't "settle" as you top-up?? if you know what I mean) then I guess we're only talking 250ml or so...therefore water'll be OK in the short term (until the service....gulp, how much is the first service??....trouble with annual services is that they tend to co-incide with RFL, Insurance renewal, et cetera!!!)
SimonKE

Will

How is there scope for error? Surely when mixing - and over the years I must have mixed several thousand gallons of the stuff - one pint of anti-freeze into a can then one pint of water must lead to a 50/50 mix!

But I agree that an exact mix is probably not essential and just topping up with water will not hurt.

Tim

I wonder how many dealers use distilled water when making up new mixes for the replacement cycle? Does the anti freeze fluid not have an inhibiter built in to counter any lime-scale etc that may be in the water?

This after all is what one does with central heating and providing that you dont keep changing the water it does no harm to the system - I installed my central heating 32 years ago using ordinary tap water and an inhibiter and today it is still in good condition .

All and Sundry.

I am fully aware of the differences between a car engine (in general and the K series in particular) and a central heating system so I shall not require any lectures on the subject:-)

Ted and the 7 year plus old Green Squirrel.
Ted Newman

Just to prevent any misunderstanding the total volume of coolant in an F is 10.50 litres (i.e. antifreeze + water = 10.5 litres).

So assuming you start with a 50/50 mixture, a one-off loss of 1 litre and the addition of 1 litre of pure water will only bring the mixture to about 45/55, hardly anything to worry about.
Spyros Papageorghiou

Simon

Just seen your reply - my header tank is happiest at a level at about half way between the bottom and the the seam - and it never seems to drop any lower BUT if it is topped up to the seam it drops back almost as soon as it has had a longish run - so I just check it every time I open the boot lid - that is the nice thing with the *F/TF* so easy to keep an eye on the coolant and oil.

Ted
Ted Newman

Simon

Already said but worth repeating: When filling make sure you only fill to the correct level, Maximum half way up the expansion tank. Only do this when the engine is stone cold! NOT after a 15 mile drive when the level drops.

I've had my 96 vvc for 16 months now and have topped up with less than a tea cup full but more than a coffee cup.

Cost of service: look on the Brown & Gammon site for their prices and add 10-20 % for an MGR Dealer if you cannot get to Baldock.
John Ponting

>> that is the nice thing with the *F/TF* so easy to keep an eye on the coolant and oil.

Exactly, Ted!! And, like yours, my header tank level has never been up to the seam....it's just that I've only just discovered that it "should" be!!

Anyway, thanx guys, I'll go out @ lunchtime and pop a bit of H20 in it and see what happens!!
SimonKE

>How is there scope for error? Surely when mixing - and
>over the years I must have mixed several thousand
>gallons of the stuff - one pint of anti-freeze into a
>can then one pint of water must lead to a 50/50 mix!

The scope is in measuring the stuff in the first place, it's OK if you start with a 5 litre jug of antifreeze and add another five litres, but if you start with a 10 litre jug and pour roughly half in, and then top it up with water...

Then you use a tap on the bottom of the container and the fluids ahve not compleatly mixed...

It all depends on how good your practices are (as indeed do most things)
Will Munns

>> after a 15 mile drive when the level drops...

So does the level DROP when the engine is hot, then??? I thought it would rise??
SimonKE

>So does the level DROP when the engine is hot, then???
>I thought it would rise?

Depends on a lot of things, the rubber in the hoses becomes more flexable, so they give more, and the pressure of the air goes up, so it pushes more. But take the cap up (no don't!) and the pressure is released, and then the level rises because the coolant is hot and therefore expanded.
Will Munns

I have to say that the water level in The Green Squirrel tends to rise when hot and drop when cool - as witnesses at the Nürburgring a couple of years back will testify:-)

Ted
Ted Newman

SimonKE - of course it rises not drops, but I had to go outside just now to look to remind myself. I cannot remember the last time I checked level when hot so brain went blank.

So, if yours is low when hot it must be very low when cold. I know it's less than a year old, has it always been like this?
John Ponting

This thread was discussed on 22/07/2003

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