What the hell is in our water?

[Russ59]

I cleaned my roof and reproofed it nearly 2 weeks ago, it beads nice when sprayed with water.
Last night I had the hose pie out watering the garden and just wafted it over my car to wash the dust off because I haven’t used it for a few days. This morning the car looks worse than before, bloody white spots all over, even my nice clean roof What the hell is in our water??

 

[javis20]

You have hard water. That's mineral deposits. I have the same problem. If I wash the car at home, I have to dry it and go over it with a quick detailer. Otherwise I go to the local car wash that has a distilled waster rinse.

 

[Old-Duckman]

You could get a water deionizing system, CR Spotless, is one brand over here in the US, there are others. You hook your water supply up to it and use it for your rinse and just let it dry...no water spotting. I have a water well at my house and the water is very hard, the deionizing works great but I don’t usually use it as it is quicker to just dry the vehicle after washing than it is setting up then braking down the system. But it does work great when I use it.

The bad thing about the water spots is, if the water is real hard you won’t be able to get them completely off with just another washing and drying. There are acid based products that professional detailers use (I’ve only heard of them, never used them) Or you can polish them out with compound and a buffer. I had to do that to my Z3 once when I had cleaned the top and let the run-off from that dry in the sun. The bonnet (hood) looked like it had leopard spots. Hand waxing did not remove them, I had to resort to the buffer. I hope yours aren’t that bad.

 

[Silverzedtom]

Definitely hard water as mentioned. An in-line scale reducer fitted to the water main will help a bit for little money - about £30 for the part. They don’t remove scale but are designed to round off the molecules so they can’t stick to things as easily.

 

[Tinker15]

Here in Yorkshire the water is soft so it’s not a problem. At out home in France it is extremely hard and is a nightmare. The XF is dark coloured (Caviar) and the first time I washed it it was a disaster zone. The only way I could get rid of the spots was to do it with a white vinegar and water mix and then polish and wax the whole car. I’m very careful how I wash the car now.

 

[enuff_zed]

Same hard water here in Norfolk.
I find if I use the hose on sprinkler, about half speed, and rinse/dry one panel at a time it's fine. Leaving it to dry anywhere is a nightmare though.
Best results I had was the day it started raining as I finished soaping it.
I used the rain water to clear off the soap, helped by a soft cloth, then wheeled it under the carport and dried it off. The difference in finish was astonishing.

 

[Jeda]

I have a similar problem in Denmark with my Sapphire Black E85. I have ender up using wet wax after the wash to avoid water and dust sticking, rinsing that off and then drying it with a microfiber towel.
This leaves a good clear finish, that last a bit longer as well in the Danish weather.

 

[IRD]

We have very hard water here in Lincolnshire which can cause scale build up in domestic appliances and leaves the dreaded water marks on cars. Our solution was to have a water softener fitted a few years ago. Costs about £50 a year for salt but it works really well. There is a company near Peterborough, I think called Race Glaze, who sell a system especially for use with cars. If memory serves me correctly it costs about £100 and the the cylinders have to be replaced periodically. It filters the water for your final rinse. They claim you don’t need to dry the car off afterwards just let it drip dry and there will be no marks.

 

[blackdog]

i have the same problem!
i tried to rinse it of but it had dried!
i couldn't even polish the marks out!
so start again and use a chamme cloth

 

[Andrew Sheldon]

I live in France and our water is very hard, we have a lot of limestone so I'm guessing its a form of limescale. Connected to our house we have a citerne, which basically collects the rain water off the roof and deposits it into a large sealed underground roofed pit. The water from that is much softer and great for washing the z4, hardly leaves a mark.. Gave it a wash last evening as a kind of celebration for finding out, after taking it off, the thermostat was stuck shut leading to clouds of steam and my head gasket, after all, wasn't blown.

 

[Dav the wheel nut]

Same in Somerset.
Marks come off easily with Poorboys polish and sealant and off windows with Invisible Glass.

 

[Jl-c]

I bought a 11L container that the window cleaners use ( long pole water filled brush on the end ) and filled it with the resin they use. Just connect it up to the hose at final rinse time, no issues, you can leave it to drip dry. Resin costs about £80 pounds a sack and a sack does 4 fills. I change it every 6 months. The water is so hard here it should come out in lumps :x I just do a hardness test every few weeks to tell how it is doing. You can gradually see it losing efficiency as time goes on.

 

[patriot66]

I have a water butt connected to the down pipe from the gutter on my conservatory. I decant this rain water off, filtering it through an old towel into a watering can. I use this rain water as my final rinse after washing and rinsing the car with regular tap water. I then dry the car with microfibre drying towels, Sonax Brilliant Shine Detailer and an airline connected to my garage compressor.
I never get a single watermark, even on our almost black Disco 4 in blazing sunshine....and rain water is free

 

[Old-Duckman]

I bought a 11L container that the window cleaners use ( long pole water filled brush on the end ) and filled it with the resin they use. Just connect it up to the hose at final rinse time, no issues, you can leave it to drip dry. Resin costs about £80 pounds a sack and a sack does 4 fills. I change it every 6 months. The water is so hard here it should come out in lumps :x I just do a hardness test every few weeks to tell how it is doing. You can gradually see it losing efficiency as time goes on.

Resin is what deionizer systems use. So you are rinsing with deionized water, it will not leave water spots until (as you have noted) the resin's useful life is over.

 

[MHZ4C]

+1 for using water from a water butt & leaving to drip dry, without any deposits or marks.
Living in a hard water area, any tap water left on the car, or running from the wing mirrors after washing, looks awful.

The rain water dries without visible residue. Connecting 2 water butts & taking water from the top of the butt helps settle out any grit from the roof before use. I wouldn’t trust the water for a wash before polishing, but for everyday washing it saves contacting the bodywork with a drying towel & saves time overall.

Will take a look at those inline resin filters. The resin was quite expensive last time I looked into it, but it sounds like the prices are more reasonable. Would much rather rinse with the hose than mess about with watering cans.

 

[MHZ4C]

OP, hope you get your z4 back to looking tip top easily!

 

[GAZA62]

Same problem here in Kent as said you have to be quick to get the car dry especially in this weather I was out there like a shot the other day as the wind changed direction an the water from the sprinkler I was using to water the garden was hitting the car but a few years back I left the car covered in water never again ended up doing a full detail to got rid of water spots I find it also gives a layer of surface rust on my brake discs after a wash.

 

[Jl-c]

I use this https://www.finerfilters.co.uk/8-x-...MI-rWXnI7c6QIVkuvtCh3V0wtlEAQYEyABEgKJH_D_BwE with this https://www.windowcleaningstuff.co.uk/water-fed-pole-systems/1117-tulsion-resin-mb115-25l.html
And yes it has gone up since I last bought it. Still worth doing though.

Edit:- it appears I lie I have just checked when I last bought resin 50 litres and it was 2014 so it lasts longer than I thought! I have 4 cars and they are usually washed and rinsed weekly, at the most fortnightly so it works out even cheaper.

 

[jimbo1958]

Here’s mine with the trolley I made for it.

 

[Bombardino]

I clean my house windows, then give then a quick once over with a diluted solution of white wine vinegar, then dry them off with a microfibre cloth, works a treat. Never done on a car though, I just resort to drying it off as quickly as possible with a microfibre towel.
The water in my house is so hard if you leave a glass of water to stand for a while you can see limescale particules in the bottom of the glass.