water usage

[nightflyer]

Hi
I have had my fourfour deisel smart car 2 and a half years and since I bought it it has always used half litre of water on approx.100 miles short journeys. I always have to top it up. If I go on a long journey it doesn't use any water. I have had the car pressure tested by Mercedes and looked at by 4 other garages but nobody can find a leak. It doesn't appear to be the head gasket or the heater matrix. It runs fine and doesn't overheat or anything. Recently I put Radwell equivalant in which guaranteed to stop leaks, which it didn't stop the water usage, but now my heater doesn't really work. Have you any answers.
Thank you

:Jan B:

[problemchild1976]

Re: water usage

When you say "heater doesn't work" do you mean that the fans work but no heat comes out?

Sounds to me like radiator corrosion and seepage and now maybe you have lost all water.

Doubt it will be head gasket - not heard of 1 of our lovely cars suffering from that?

JJ

[Thrumbleux]

Re: water usage

Hi
Recently I put Radwell equivalant in which guaranteed to stop leaks, which it didn't stop the water usage, but now my heater doesn't really work. Have you any answers.
Thank you

:Jan B:

Chances are the Radwell has blocked the heater matrix core.
Never use that stuff - it's rubbish. Fine for a 1940s tractor but has no place in the modern world. Try back flushing the matrix after first checking the inlet to it is hot enough to provide heat.
Not absolutely certain that the above is your problem, but its what I'd check first.

Re the original problem. Your description implies no leak once up to heat suggesting leaking only when cold. To eliminate head gasket as potential leak - is there any sign of water in the engine oil?

[Fudge]

Turbo next....




Fudge!

https://www.fudgesmart.co.uk

Sent from my iPhone4s using Tapatalk

[davros7760]

Re: water usage

A mate came across an almost identical problem and was confused
because (like thrumbleux) he was half expecting water in the oil.

Eventually he found a small hairline split in a hose which would weep water
until the connecter heated up expanded and for some bizarre reason pushed the
split shut.

The water is going somewhere - have you considered cleaning up the engine and then
looking for the deposits evaporating water leaves?

Don't envy you getting to the bottom of that problem, though at least the car is running

[nightflyer]

Re: water usage

Thank you for the reply. I will try back flushing. Hate having no heating. There is no oil in the water. No water coming out of exhaust. Hoses checked. New radiator cap. Mercedes pressure checked it. Strange one this. Car runs great.
Thanks for your help.
Jan

[nightflyer]

Re: water usage

Hi
Thanks a lot for that will get my husband to do what you suggest.

Kind Regards
Jan

[nightflyer]

Re: water usage

Thanks for the reply. The fan is working and there is water in the rad. Will keep looking. Car runs great. Will check the hoses again. There is no water on drive when standing.

Thanks again
Jan

[madDan]

Re: water usage

any on the under tray where you can't see it?

Also have a good look at the thermostat where the pipes join on occasionally they weep there and the heat dries off the water, tell tail signs of white dry deposits.

[problemchild1976]

Re: water usage

Let us know if you solve the issue. Then I cn put the info up on our forfour site to help out others

JJ