W204 250 CDi Loosing coolant...

[moj91]

Hi all,

Past few days I've had a low coolant warning message on start up in my C250 Cdi,

I've had a quick look under the bonnet but cant see any blatant leaks...

I've also noticed that the coolant that is in the header tank is a tad murky.

Are there any common coolant loss issues with this engine does anyone know? Hopefully with a heads up I can avoid a wild goose chase!

Thanks!

 

[Uncle Benz]

Water pump is a known issue on these.

 

[moj91]

Were there any recalls on this? If it turns out to be a water pump failing, on a 38k engine that is a disgrace...!

 

[AMGeed]

As Uncle Benz has noted, the water pump would be the first place I'd look. The smallest leak is almost unnoticeable but will get worse with use.

It's not the mileage of 38k that is the factor. Your car is 5 years old and ancillaries like the water pump can and do fail.

 

[geraldrobins]

I had mine replaced at 36k, 3 years, under warranty. I hadn't noticed a leak but when in for service the dealership advised they had changed it as it was starting to seep.

 

[Scruffyalfa]

Yep water pump changed on mine too at less than 30,000 miles, also egr and some other widget. All 3 had a leak under pressure test and MB kindly changed them for me.
Started with drop in coolant level and error message but it was flagged up under the MB 'Club' check over.

Never had one go on the Alfas though and they are supposed to be unreliable.

 

[moj91]

Regardless, a water pump failing at such a low mileage, including those of you at 30k on newer cars, is pretty poor on Mercedes' part. You should be able to expect such a component to last 90k easily. I've never seen one fail on anything less than 110k... Independent said that it was a component that was part of the fuel filter assembly that had failed upon pressure test, and has been replaced.. yet this morning, again, Low Coolant warning. Ive topped it up and will monitor it over the next few days and see if that was not just a one off from the system being drained and refilled...

 

[AMGeed]

Regardless, a water pump failing at such a low mileage, including those of you at 30k on newer cars, is pretty poor on Mercedes' part. You should be able to expect such a component to last 90k easily. I've never seen one fail on anything less than 110k... Independent said that it was a component that was part of the fuel filter assembly that had failed upon pressure test, and has been replaced.. yet this morning, again, Low Coolant warning. Ive topped it up and will monitor it over the next few days and see if that was not just a one off from the system being drained and refilled...

That would suggest to me that the water pump may still have an issue as coolant loss shouldn't be blamed on a fuel filter assembly.

I agree an ancillary like a water pump should last a long time, but it appears they are a weak link on the W204. Blame the supplier I suppose, as MB don't make them.

 

[Scruffyalfa]

You could blame the supplier but iMB are approving them for use and are liable for any premature failure.
Fuel filter housing was the other 'widget' that leaked on mine, surprising that this housing was anyway connected with coolant.

 

[geraldrobins]

Mine is a 2011 facelift model so would have hoped that any water pump design weaknesses or manufacturing issues would have been rectified by now as the w204 has been around since 2007/8. It seems not.

 

[star]

Water pump, fuel filter housing/pipe and water cooled egr gasket are all common coolant leak points.

 

[Scruffyalfa]

Out of interest Star what time and cost is involved to change these items?

 

[coventryslk]

All ok on the om646evo engine though and easy to change.