Bad advice?

[Hooversquirrel]

My sister told me she kept getting a warning light on her dash informing of low coolant level, she drives a BMW 530d.
Her handbook didn’t detail what type she should use so I checked internet, most advised Comma G48. I use this is in my Z3 so am aware it’s blue coloured whereas what’s left in her car is pink. I suggested she shouldn’t fret too much about the colour difference but further research suggests that the blue if added may emulsify. Have I given poor advice? ( the car is in for a service next week anyway, I felt the most important factor was not to allow car to overheat due to lack of coolant...)
Thanks

 

[the Nefyn cat]

Never tried mixing colours of coolant, I've heard that it's a bad idea. And I wouldn't trust the sensors, known too many of them tell lies, go to top something up and the level's not down. My 330 keeps telling lies, all down to sensors, change the sensor and it comes back a year later.

 

[mrscalex]

I don't think cross-mixing small amounts is going to do any damage. But there are 2 alternatives. If it's only a small amount needed then plain water is not going to affect the concentration. You can also get all-type top-up bottles.

If there is a significant amount of coolant loss then I expect you'll realise you have bigger things to worry about.

 

[Sean d]

I've never used anything other then water, tap water that is, come winter I add antifreeze, strange thing is, I have never had a coolant issue

 

[mwpe]

Use of tap water depends on what part of the country you are in, if you live in a hard water area like us in the south, it will fur up the engine quite quickly.

 

[mrscalex]

Use of tap water depends on what part of the country you are in, if you live in a hard water area like us in the south, it will fur up the engine quite quickly.

Swindon is one of the worst parts of the country for calcium content/hard water. I bring it back from Swansea, one of the softest in a big water container and use that for steam iron and cars.

 

[Sean d]

Use of tap water depends on what part of the country you are in, if you live in a hard water area like us in the south, it will fur up the engine quite quickly.

This is where I disagree Mike, it's a sealed unit, so once the water is in it only has so many impurities, it's not like a kettle that is continually depositing lime scale as its topped up several times a day

 

[Hooversquirrel]

Thanks for the input guys

 

[Paul Rice]

Use of tap water depends on what part of the country you are in, if you live in a hard water area like us in the south, it will fur up the engine quite quickly.

We have Holy water upt North

 

[Nodzed]

This is where I disagree Mike, it's a sealed unit, so once the water is in it only has so many impurities, it's not like a kettle that is continually depositing lime scale as its topped up several times a day

Sorry strongly disagree Sean. It takes very little amounts of foreign bodies to reduce flow or block a rad, tap water can affect different parts of the cooling system in different ways, and can cause, through reaction further impurities to be produced as time goes by, therefore increasing the impurities in the cooling system (rust being one where no inhibitor is being used)

I personally wouldn't use tap water, I buy distilled water, its cheap, if using antifreeze, or I use a premixed coolant. I certainly would not recommend using only tap water and nothing else in an engine regardless of the time of year, we call it antifreeze but it is also an inhibitor for corrosion and wear, it does so much more than just stop the water freezing.

No engine manufacturer will advice using tap water or running without inhibitors.

 

[Delk]

Water quality will have a small effect but you defiantly need an additive to stop corrosion and other issues. Even if you are mixing different types of additive something is far better then nothing.

On a side note I had a warranty issue years ago with MTU in Germany over some generator heat exchanges. We had replaced two very expensive heat exchanges and they both failed in a couple of months. They originally turned down the claim stating that we were using the incorrect additive that was only available from them and this caused the failure. After a prolonged discussion the two coolers were sent back to Germany for inspection.

I received a nice report with photos showing corrosion on one side of the exchange cores with a claim that it was from the incorrect treatment.

One phone call later and they sent me two new heat exchanges free of charge. The photos were of the sea water side of the heat exchanges and they couldn't tell me how much chemical to add to the Atlantic Ocean.

 

[Sean d]

Sorry strongly disagree Sean. It takes very little amounts of foreign bodies to reduce flow or block a rad, tap water can affect different parts of the cooling system in different ways, and can cause, through reaction further impurities to be produced as time goes by, therefore increasing the impurities in the cooling system (rust being one where no inhibitor is being used)

I personally wouldn't use tap water, I buy distilled water, its cheap, if using antifreeze, or I use a premixed coolant. I certainly would not recommend using only tap water and nothing else in an engine regardless of the time of year, we call it antifreeze but it is also an inhibitor for corrosion and wear, it does so much more than just stop the water freezing.

No engine manufacturer will advice using tap water or running without inhibitors.

Horses for courses pal, like I said, I've used tap water since I started driving 35 years ago, never had a coolant issue, you will find a lot of old school trade do the same, I must admit to having some type of antifreeze in it though

 

[mwpe]

As I said Sean, it depends on what part of the country you are in. You probably live in a soft water area, down here the water produces so much limescale I wouldn't use it in the BMW. I must admit to having used it in the past but wouldn't now. I once rescued a Hillman Imp which was due to be scrapped because of overheating. I removed the radiator and filled it with kettle descaler and and after it had been left for an hour or so and flushed all was well. On our cars the additives in the coolant are important.

 

[gookah]

I only use the water from BMW garages, along with their air for the tyres, anything else is not recommended.
its only £100 a litre, and £20 per tyre,
Also, on the service, the £5 to top up the already full washer bottle,
Always worth the extra in my opinion....

Besides, by giving my card and pin number to that nice Asian, to protect my recently hacked bank account, I can now at least safely know, that as sole recipient of my recently passed Nigerian uncle's Will money, it will soon be in there, and will cover these little extras.
No flies on me!

Oh, and I did find that 'gullible' word in the dictionary that my mate said wasn't there.
ha, made him look stupid when I showed him.
Some people!

 

[Sean d]

I only use the water from BMW garages, along with their air for the tyres, anything else is not recommended.
its only £100 a litre, and £20 per tyre,
Also, on the service, the £5 to top up the already full washer bottle,
Always worth the extra in my opinion....

Besides, by giving my card and pin number to that nice Asian, to protect my recently hacked bank account, I can now at least safely know, that as sole recipient of my recently passed Nigerian uncle's Will money, it will soon be in there, and will cover these little extras.
No flies on me!

Oh, and I did find that 'gullible' word in the dictionary that my mate said wasn't there.
ha, made him look stupid when I showed him.
Some people!

Love it, nearly spat my tea out

 

[mrscalex]

As long as people have both schools of thought then they can make their own decisions. But I know what the water does to things in Swindon - it destroyed my last steam iron. It's the hardest in the country. If I can bring the country's softest water in the country back for free from Swansea then I'll use that. However I would think timely changes of the coolant with fresh antifreeze are the more important factor.

This is a good map showing where the water is softest and hardest in the UK.

 

[Sean d]

As long as people have both schools of thought then they can make their own decisions. But I know what the water does to things in Swindon - it destroyed my last steam iron. It's the hardest in the country. If I can bring the country's softest water in the country back for free from Swansea then I'll use that. However I would think timely changes of the coolant with fresh antifreeze are the more important factor.

This is a good map showing where the water is softest and hardest in the UK.

View attachment 134737

But its relative to how many times you fill an appliance, a kettle is filled and boiled continuously leaving lime scale deposits from thousands of gallons of water over its life span, how often do you change the water in you z

 

[mrscalex]

But its relative to how many times you fill an appliance, a kettle is filled and boiled continuously leaving lime scale deposits from thousands of gallons of water over its life span, how often do you change the water in you z

I'm not making the case for one way or another. But since I bring the water back for my steam iron it might as well be used in the Z3s too.

The turn over of water in my steam iron (generator) is relatively low as I don't get round to do the ironing that often. But it was destroyed completely after maybe 30 fill-ups. It really is that bad in Swindon. So it's essential for that.

 

[the Nefyn cat]

I spent 25 years living in Folkestone, and got used to having to buy a new kettle once a year. Now I live up here, and the inside of my kettle (can't remember how old it is) is like new. No worries about using tap water in a car here.