Topping up coolant

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ash1212002

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Car
W204 c250 cgi facelift petrol 2011
Mercedes c250 2011 cgi facelift petrol saloon

Need to top up the coolant as had a warning on the dash today to top up

Will the euro car parts TRIPLE QX Blue Antifreeze/Coolant be suitable? or shall i stick with genuine mercedes coolant?

1 litre from ecp can be purchased for less than £5

Whereas the merc genuine coolant, cheapest i found on eBay was £19 for 1.5 litres!
 
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If you need to top up the coolant then you will need to find the source of the coolant loss - there should be no need to top coolant up.
I would top up with a measured amount of distilled water; then find and fix the source of the loss and then replace the coolant with new MB coolant. It will be most likely that the cooling system will need to be drained to fix whatever the problem is.
 
If you need to top up the coolant then you will need to find the source of the coolant loss - there should be no need to top coolant up.
I would top up with a measured amount of distilled water; then find and fix the source of the loss and then replace the coolant with new MB coolant. It will be most likely that the cooling system will need to be drained to fix whatever the problem is.

Oh dear, i thought it may just need a top up as I've never touched it, looks like half a cup full has been lost

Are there any areas on this particular engine which I should look at to determine where the leak is coming from?
 
On the OM651 diesel is common for the water pump to leak. Its possibly the same issue, The leak is seen mainly when the engnie is cold, it seeps out but not seen when warm.
Not usually mega expensive to replace in the grand scheme of things.
 
If you have just lost a small amount then top up with distilled water, if light comes back on you
will need to investigate further,,,
 
Will have a look this morning, where is the water pump located on the c250 petrol engine?

Apologies if this is a stupid question couldn't find distilled water on ECP or Halfords found deionised water, is this the same? Doing a quick google search it appears to be two different types of water?
 

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Found the location of the water pump, no signs whatsoever of any coolant residue, is it worth removing the bolts to have a closer look?

Looked around the engine/coolant pipes no signs of any leak

I think I'll top it up with the ionised water and monitor
 

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This is good advice, just use distilled water, and then try to find where its leaking from. Its a bad idea to mix different anti-freeze's, as some are not miscible, and can cause problems. Can you check if the coolant was ever changed in your car? If so then you can replace like with like, and thats safe enough. Don't assume that just because it's the same color, it's the same anti-freeze. There is a coolant change schedule as far as I know...anti freeze is not a "for Life" item. On my last merc, I changed and flushed the system, and refilled with MB approved 325 spec, Comma G 48. So I know exactly what to replace it with, if it needs topping up.
 
Before you get involved in looking for leaks that you may not have, I would simply top up and keep an eye on the level...if it drops, then start looking for the reason
 
I'll top up with ionised water and monitor. I've got a 130 mile drive so will check after and report back
 
I'm doing the very same thing with an E Class I only bought last week....yesterday the "Low Coolant Level" warning light came on, so I marked the level it was at with a permanent marker, and measured the amount that I put in, ( 425 Ml.) noted the mileage and date, and now I'll drive it for awhile and see how it goes. While the waterpump is a common leak culprit, in the diesels there is a heating element in the fuel filter housing ( the coolant circulates around the filter) and this is also a common cause of water leaks, And it leaks without much visible sign of the leaking, because it tends to happen when the car is moving, and so any drops are quickly dispersed.
 
A while back I had the coolant level light come on when the car was on a steep hill. First time in 5 years, so I topped it up with a small amount of de-ionised water, can't have been more than 2 - 300 cc. I've kept an eye on the level in the expansion tank and it seems to be holding up.

Colour is no longer a reliable indicator of coolant chemistry but the old type of cheap blue coolant is definitely the wrong stuff as it only lasts 2 years. MB coolant lasts 10 years.

If you want to judge the quality of Triple QX coolant, look at how long they claim it will last. I suspect it will be 2 years.
 
I consulted the MB spec for coolant and both distilled and deionised water were acceptable but as you say they are not the same.
 
I consulted the MB spec for coolant and both distilled and deionised water were acceptable but as you say they are not the same.
It’s important for battery water to not have touched metal, you may or may not have seen at service station signage stating water not for batteries, I don’t know why but I’ll never forget being told
 
For battery's, the ideal is distilled / ionised water, but over the year's, when neither was available, I used ordinary tap water, and no side effects ever that I noticed. But car Cooling Radiators are a different kettle of fish... Not only does the coolant have to have anti-freeze properties, but also anti-corrosion properties as well, And they are designed to suit different metals, so depending on what metals are used in the engine, will define what chemicals that can be used in the fluid. Always consult your manufacturers booklet, or ask the dealership about which which is the correct fluid for your car. There are plenty of horror stories circulating about the effects of mixing incompatible brands of anti-freeze in your engine. Color now is basically meaning less, so do not depend on the red antifreeze in the container as being the same as the red antifreeze in your radiator., its the chemical composition which counts.
 
Topped up the coolant to max with deionised water before my 130 mile drive yesterday. Checked the coolant level this morning and it hasn't dropped!

Will continue to monitor over the coming weeks/month's...
 
Topped up the coolant to max with deionised water before my 130 mile drive yesterday. Checked the coolant level this morning and it hasn't dropped!

Will continue to monitor over the coming weeks/month's...

The coolant level in my last MB sometimes took as long as 3-4 mths before needing to be topped up, and it never showed where it was leaking from, but the likeliest place was the heating element in the fuel filter. And same with the new car.. no visible sign's of a leak...yet anyway. So wait and see time.
 
I live in Aberdeen and have never ever use distilled water. I have always used tap water with no ill effects. Now tap water down South that's a different storey.
Use tap water at your own peril.
 

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