Contaminated coolant water

[Rifleman]

When my 2yr old Superb went in for its annual service the dealer found that the coolant system was contaminated. It is a cloudy, murky dark olive green colour. A bit like muddy green puddle water. There is no evidence of any oil in the coolant. If you dip your finger in it it just feels like normal runny water. Oil level is normal, it’s not used a drop from new. Likewise for coolant, never needed topping up.

 

The dealer had it back in for a warranty service to flush out the system and replace the coolant but they made no attempt to discover the source of the contamination. 1000 miles on, during a return trip through France, the car started beeping a warning and flashing warning signals saying the coolant was low and needed refilling. It took 1.5l of water to top it up. That was 3 weeks ago. Checked the coolant level again yesterday and it took about 250ml of water to get it back to normal.

 

I’ve booked the car in so the dealer can have another attempt at fixing it.

Anyone had a similar problem with contamination and if so did you find the source of the problem?

[Ootohere]

If you had the car from new so know the incorrect coolant was never added or Rad-Weld / K seal or any other additives,

has it never been in the keeping or care of others?

 

Where did you get the 1.5 litre of water you added, from a domestic tap, bottled water or at the likes of a a filling station from a container?

Edited 22 July, 2018 by Offski

[Rifleman]

11 minutes ago, Offski said:

If you had the car from new so know the incorrect coolant was never added or Rad-Weld / K seal or any other additives,

has it never been in the keeping or care of others?

 

Where did you get the 1.5 litre of water you added, from a domestic tap, bottled water or at the likes of a a filling station from a container?

Always in my keeping apart from when it goes to the dealer for servicing.

Added water was from a sealed 1.5l bottle of drinking water bought at a motorway service area....

[lohr5000]

Any signs of excessive grey smoke from the exhaust?

Or water leaks around or under the engine/radiator?

 

If it isn't leaking from the cooling system, then I suspect it could be a head gasket problem, especially as you mentioned the water was contaminated.

A simple leak wouldn't cause the contamination.

[Ootohere]

Good that a Tech at the dealership first discovered it at an annual service,  nothing to do with them, no 'fitter' involved in the service or the likes, just the green was found while the

coolant was being checked, unless the color was obvious, or the top was off and the Min / max level being topped up .

Then they did the flush and refill, and now they can be sure whatever the fault is is fully repaired. 

[Rifleman]

16 minutes ago, lohr5000 said:

Any signs of excessive grey smoke from the exhaust?

Or water leaks around or under the engine/radiator?

 

If it isn't leaking from the cooling system, then I suspect it could be a head gasket problem, especially as you mentioned the water was contaminated.

A simple leak wouldn't cause the contamination.

No smoke, no obvious water underneath.

I’m no mechanic but I suspect the water level warning was due to them not fully tightening something when they performed the flush causing a very slow leak somewhere.No problem at all with coolant level until that was done. Any slight drips would have evaporated very quickly in this heat.

 

I may be imagining it but I get the feeling that the engine does sound a little louder than usual, hard to describe but a sort of low growl/grumble sound under load...

 

Fingers crossed they will put a mechanic who knows what he’s doing on it ;0)

 

[xman]

3 hours ago, Rifleman said:

 

The dealer had it back in for a warranty service to flush out the system and replace the coolant but they made no attempt to discover the source of the contamination. 

 

 

Extremely poor service, obvious serious problem in a 2yr old car and they didn't analyse the coolant? There are are kits to test for contaminants, its likely you have a blown head gasket or cracked head, now losing coolant. 

 

Maybe they were hoping you could make it to year 3 so deny you warranty. (Hope they don't use the "you didn't top up the coolant with the correct stuff" card)

[Rifleman]

A question for you tech-savvy guys (sadly I’m not one of you), if the head gasket is blown would you expect cross contamination i.e. oil in the coolant, water in the oil?

[FelisBengalensis]

It depends upon where the gasket has failed (or crack is growing) and the pressure environment at that spot.  If there is no oil gallery close by then you may just get exhaust products and/or fuel contamination, plus oil from the bores perhaps, in the water.

 

If there is any sign of ‘mayonnaise’ (oil/coolant emulsion) on the oil filler cap then coolant is getting into the oil.  That is a definite sign of head failure in one way or another.

[cheezemonkhai]

Is it a diesel?

 

if so what about the EGR cooler circuit?

That could lead to some pretty nasty coolant if there was a small crack in the heat exchanger on older cars.

 

on a mk2 pd140 I had a weld on the radiator that opened up when hot but closed again when cold. It dumped coolant twice before it was diagnosed and fixed under warranty.

 

 

Edited 23 July, 2018 by cheezemonkhai

[Rifleman]

The car went into the dealers today for the coolant contamination to be investigated. Their conclusion, it’s definitely contaminated again but they don’t know why! They ran a diagnostic check which didn’t show any other problems.

 

They spoke to Skoda UK about what to do next as it will be a warranty claim. Skoda told them to repeat the flushing and try again. They’ve booked it in for 2 days on 20th August. That will be 19wks after they first found the contamination.

 

It’s getting very close to the day where my trade-in takes place on a new car (which is not a Skoda). I can see this being a real problem...

[FelisBengalensis]

They need to sample the water and identity the contaminant.

 

I’m not surprised about a fault log being blank, they probably don’t have any sensors that can pick it up anyway.  It really worries me that so many ‘Technicians’ are clueless if the computer says no, as are the main UK Support Teams.  In the good old days you would do a pressure check and look for leaks between the cooling systems (oil & water) or into the gores. It isn’t difficult.

[Rifleman]

Ahh, the good old days.

Nostalgia ain’t what it used to be... 

[FelisBengalensis]

And I meant ‘bores’!  Blasted auto correct 

[Danielctaylor]

Hi rifelman

Did your coolant contamination issue ever get sorted by skoda? At the moment it is bleeding me 700£ each trip,possibly monthly with no known cause or permanent fix.

Kind regards, 

 

Dan

[boydeee]

Could this not be the silica bag that sits inside the coolant reservoir? If it bursts, it turns the coolant brown I believe. I've seen Golf owners with the same issue as you describe 

[Danielctaylor]

Not sure to be honest. I have not checked the bag status. Is it easily visible? Can it be changed or the whole tank needs changing? 

[boydeee]

If you take the cap off, it sits in the middle in a hollow. I believe if it's burst a system flush would be required and possibly some new parts but I am not sure I'm afraid. 

 

I've seen a video of a guy removing it but it looks hard work!

[Danielctaylor]

Thanks I'll have a look. Decided to take it to an independent garage. Main dealership either clueless or all in collusion. Whenever I see a smart new dealership showroom all I think of is, if they can't sustain it via sales then it must be via services.