Scum in coolant reservoir

[Spinifex]

Did my weekly check of the Octy yesterday morning before taking it for a long drive. It's done a total of 1200km.
Oil looked super clean and hadn't moved in level since I collected the car a month ago.
BUT
Found this oily smelling and oily feeling fluid inside the coolant reservoir, and all this scum floating on the top of the red coolant. Immediately panicked that the engine was blown - I've heard of water in the oil before, but never oil in the water.

Urgent call to Skoda service dude at the dealership and described it, and he assured me that if the temp gauge never moves (it sits on a dedicated 90degrees) and the coolant level (without the scum) was between the min & max markers, then it was completely safe to drive.
He described the scum as remnants of slight lubrication fluids left inside the cooling system when the car was manufactured, which has just mixed with the coolant and caused the sludge.

What he described sounds reasonable to me, but I just want to know if anyone else has encountered this before?
I've had previous engines rebuilt & refitted and never found that in my coolant.

It's due for it's complimentary 1500km inspection (it's not really a service) next weekend, so I've asked them to make sure they do a complete drain, flush & refill of my cooling system, which they've agreed to do.

[HPRS230]

Interested to know the out come mate, it doesnt look good.
Personally, Id be dropping water and oil asap and sending it to Brisbane on a tow truck (battery off/fuse out so it cant start).
You don't want water where oil is, or oil where water is...

[Umai Naa!!]

Possibly an oil cooler failure.

I probably wouldn't be driving it.

They're going to have a hell of a time getting oil the oil out of the cooling system, even with the special detergent they use.

Oh yeah, and don't touch anything. Leave it as is, and let them diagnose it accordingly.

[Spinifex]

Yep I agree it doesn't look good.

Have emailed them some more photos I took tonight - I've driven about 350km further since he told me yesterday it was OK to drive, so we'll see what they say tomorrow when they see the photos.

The sludge is very smooth and runny today - yesterday it was lumpy like soggy old cereal.

Coolant is still above minimum level, but is lower than it was yesterday - and the sludge layer looks thicker than yesterday too.

[Spinifex]

Possibly an oil cooler failure.

I probably wouldn't be driving it.

They're going to have a hell of a time getting oil the oil out of the cooling system, even with the special detergent they use.

Oh yeah, and don't touch anything. Leave it as is, and let them diagnose it accordingly.

Agreed. I bought a new car so I wouldn't have to be fiddling around with it myself anymore!!!

It'll be parked up until they respond to my email tomorrow regarding the photos I sent. If they say it's all good, then I'll take their word for it. It's under warranty, but I'll be making sure they clean/flush the system SEVERAL times this weekend, before refilling. I don't ever want to see that crap in there again!

[Umai Naa!!]

Hard to say exactly what's gone on with this one. I'm not aware of any such issues on these motors.

The sludge under the cap, could just be normal condensation that's mixed with the oil residue on the cap itself. Normally not a big deal. Has the oil level risen on the dipstick? This would suggest that the coolant and engine oil have mixed both ways.

[Spinifex]

Nope - oil is the same level it's been since day one

[ScotRok]

Head gasket most likely failed, I have seen it on other cars. It's emulsion from the oil and water mixing.
Have a look at the oil filler cap for the emulsion too.

[Spinifex]

Thanks ScotRok. I didn't think to check the oil cap - only the dipstick.

Will do that when I get home tonight.

[ScotRok]

That's too much gunk to be residue from manufacturing.