My coolant level is below the minimum level so need to top this up. Is there a difference between coolant brands eg: Will Halfords long life be a fine substitute to BMW one or is it better to stick to the BMW one for consistency ?
Coolant, difference between brands?
- Thread starter mrk
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I did wonder why it was low but then I don't remember checking the level before either so it may well have been low to begin with. Would the fact that I checked it at lunch cause the level to vary within the system?
I drove to work on the motorway so the engine had not cooled down completely yet but cool enough to open the coolant cap.
I looked also high and low for leaks or any streaming and saw no sign of anything of the sort, completely dry even after the rainy drive to work.
So does coolant not naturally go low over time ?
I've tried to google with mixed results, some say use bmw only others say no difference but there are 3 types of coloured coolant I read, green, blue and orange hence the confusion!
Ok will do, I think you might be right though since the coolant indicator light has never come on either even though the dipstick shows to be below minimum. if I lift the dipstick with my fingers and let go it drops to rest. I will see again in the morning.
Water? :O It's meant to be an even mixture isn't it!
It's the latter (didn't think BMW did a different one on any engine really). The silly float/dipstick thing has 2 ball-like bits, one for min level and one for max. The top ball (max) is below the tip of the min marker, well from what I can interpret from the very handy diagram next to the cap!
[TW]Fox;12475111 said:
It's the latter (didn't think BMW did a different one on any engine really). The silly float/dipstick thing has 2 ball-like bits, one for min level and one for max. The top ball (max) is below the tip of the min marker, well from what I can interpret from the very handy diagram next to the cap!
I phoned up a local dealer and a 1.5litre bottle of coolant is just over £7 so will pick up a bottle in the morning if the coolant level stays as it is !
I'm not confident topping up with tap water alone, I've see what limescale does to the household iron !
I'm not confident topping up with tap water alone, I've see what limescale does to the household iron !
Well the level was the same this morning so picked up some coolant on the way to work will top up during late lunch.
I have a spare bottle of spring water, I guess this is just as good to use as distilled /deionised water plus I don’t really take a measuring jug with me to work so the bottle serves a dual purpose
I have a spare bottle of spring water, I guess this is just as good to use as distilled /deionised water plus I don’t really take a measuring jug with me to work so the bottle serves a dual purpose
I've checked for leaks and there is no signs of any leak anywhere. All other fluids are normal too. I will however go to a local garage for a compression test just to be on the safe side but I'm pretty confident that it's just /low coolant/ to begin with though but will find out for sure soon enough!
Ok ,
Reading around various places I have learned that if the previous coolant top up or change done by the last owner had a non standard mixture of water/coolant (more water or bad quality water! than the recommended amount for example) then the water could have evaporated to some extent over time during heavy driving sessions resulting in water loss.
I doubt it’s any leak or gasket/valve fault because the engine light on BMW is quite outgoing even if the fuel mixture is a bit off it will light up and run the engine more lean.
Since I have no signs of a leak anywhere I am quite happy by the above so I will top up the coolant using the correct mixture and using de-ionised water and then just monitor the level over a month or so.
Reading around various places I have learned that if the previous coolant top up or change done by the last owner had a non standard mixture of water/coolant (more water or bad quality water! than the recommended amount for example) then the water could have evaporated to some extent over time during heavy driving sessions resulting in water loss.
I doubt it’s any leak or gasket/valve fault because the engine light on BMW is quite outgoing even if the fuel mixture is a bit off it will light up and run the engine more lean.
Since I have no signs of a leak anywhere I am quite happy by the above so I will top up the coolant using the correct mixture and using de-ionised water and then just monitor the level over a month or so.
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BTW I've covered almost 5000 miles since I got the car which was 28th July and I could not find any pages online that state if driving long distances in short spaces of time can evaporate certain fluids. Anyone confirm?
Hmm people have mentioned this a few times in the thread that coolant should not drop and this concerned me so had a quick phone chat with local snows bmw service who said it's normal for the coolant to drop and should be checked every month and topped up as required. I did mention the current level of coolant remaining and he said it’s normal and I’d need around half a litre of 50/50 mixture water/coolant.
I mentioned since it’s a closed system it should not be going anywhere and he replied that it will still evaporate through microscopic holes in a similar way to how tyre pressures become low over time.
I'm no super expert on how engines work but does this sound fair? I know the same might not apply to all engines but in general for this type of engine especially as some people have said their levels have not dropped at all?
Can anyone call up their local dealer to see if they say the same as well ? would be interesting to see if you are told something different!
I mentioned since it’s a closed system it should not be going anywhere and he replied that it will still evaporate through microscopic holes in a similar way to how tyre pressures become low over time.
I'm no super expert on how engines work but does this sound fair? I know the same might not apply to all engines but in general for this type of engine especially as some people have said their levels have not dropped at all?
Can anyone call up their local dealer to see if they say the same as well ? would be interesting to see if you are told something different!
Ok a quick update.
I know now why the collant had dropped.
It had evaporated! I know this because when I was in London on Thursday I checked the coolant level, it was the same level as when I topped it up earlier on in the thread (normal) but what I forgot to do was close the coolant filler cap up tightly so it was evaporating away!
This morning the coolant level light came on when starting up the car and I was dreading the thought of a leak over the last 200~ miles but when I went to re-top up found the filler cap was loose so I had indeed forgotten to tighten it shut hence why the coolant level dropped so much in the course of a few days!
Needless to say, I have topped up again and tightly closed the cap.
Looks like it does indeed evaporate away either slow or fast depending on how the cap is put back on. IIRC it is pressurised so if the cap is not on tightly it's not going to help much!
I know now why the collant had dropped.
It had evaporated! I know this because when I was in London on Thursday I checked the coolant level, it was the same level as when I topped it up earlier on in the thread (normal) but what I forgot to do was close the coolant filler cap up tightly so it was evaporating away!
This morning the coolant level light came on when starting up the car and I was dreading the thought of a leak over the last 200~ miles but when I went to re-top up found the filler cap was loose so I had indeed forgotten to tighten it shut hence why the coolant level dropped so much in the course of a few days!
Needless to say, I have topped up again and tightly closed the cap.
Looks like it does indeed evaporate away either slow or fast depending on how the cap is put back on. IIRC it is pressurised so if the cap is not on tightly it's not going to help much!
The coolant reservoir is pressurised, with the cap on hardly at all (only placed on top and marginally turned so it doesn't fall off) it's not going to pressurise the reservoir and the liquid can evaporate away in the hot engine bay which is what happened it seems.
I drove around London, Luton and St Albans during this time all long journeys at motorway speeds too so suppose it's to be expected.
I drove around London, Luton and St Albans during this time all long journeys at motorway speeds too so suppose it's to be expected.
That leads me back to what the Snows BMW service dept guy told me on the phone back then about it escaping over time through microscopic holes so eventually will need topping up!
Well you will get steam burn injuries if you open the coolant cap on a freshly driven engine so therefore evaporation!
Well you will get steam burn injuries if you open the coolant cap on a freshly driven engine so therefore evaporation!