[Solved] Scania R440 XPI E5: Creamy Slime in Expansion Tank, Corroded Pipe & Retarder Issues

Hello.
Scania R440 xpi E5 in the expansion tank there was a creamy slime, low level of fluid in the cooling system noticed after the message, I added about 1 liter, a little corroded pipe sweating ...
I would like to add that the car has a retarder and I used it, after noticing this slime, removing it slightly if possible on the road, the retarder turned off and not used for 2500-3000 km, the new foam was gone. The oil level in the retarder is minimum, the mechanic added 2 liters. Now a similar route, on the return, a retarder will be used to see what will happen in the expansion tank and with the oil level in the retar ...
Maybe someone dealt with a similar case ?!

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Photo of this goo [Img]

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[url=https://obrazki.elektroda.pl/6974409400_1518962184.jpg]

The only place where fluid and oil are close to each other is in the rotarder cooler.

Check the oil in the gearbox. Maybe the box oil cooler has come off. It is on the right side of the engine under a cover behind the air compressor.

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Here's a drawing.

Which year of production is it?

To be precise, the gearbox oil cooler looks like this:

2007 year of production, first registration 2008.935 thousand km mileage. I will come back and check the oil in the box. Thanks for the answer and your interest.

Give me my chassis number.

And here is the engine:

No. Vin: 2033099

I corrected the photos, they are selected according to the vin number. They differ in a few elements, small but always different. For that you needed just the vin number.

I understand. Thank you...
Tomorrow, after driving a few hundred km, using the retarder, I will write if something has appeared, maybe with your help we can determine the specific cause ...

Only today, on a section of about 150 km, I used a bit of a retarder, because the terrain and an empty car did not allow for more. After unscrewing the cap from the expansion tank, quite high pressure in the cooling system. By not using it, for example, driving 600km, there was no pressure. So first, remove the retarder cooler and check for leaks ?!

That would be the case, but check the oil level in the retarder beforehand.

The level of the oil in the retarder in the center of the dipstick, i.e. 1 liter is lost during the short use of the retarder. There is oil in the box, after unscrewing the screw it did not leak, but you could feel it with your finger just below the hole.
Removing the retarder cooler is very complicated and time consuming ?! Because I think I will have to deal with it myself, the car stopped a week earlier at the workshop and due to the heavy workload they did not have time to see or diagnose.

You have to check the oil in the retarder warm or cold, you must always check under the same conditions.

I checked with cold oil, the mechanic had also added cold oil earlier, following the scale for natural oil

Hello. The problem is solved, I close the topic. It turned out that the compressor head was damaged, released oil into the cooling system, the next symptoms were too high pressure in the cooling system and fluid ejection after unscrewing the expansion tank cap, you could observe small bubbles on the running engine. To be sure that it was a compressor, I closed the coolant circuit bypassing the compressor, started the car, and stuffed foam from splashing soapy water into the hoses coming from the compressor head. Bubbles from both hoses confirmed its leakage. I bought a new head from Majorsell Skuba for PLN 950 net. After the exchange, it is fine. I regret a bit that I drank and did not buy a whole new compressor from this company for PLN 2600 net. I checked the retarder earlier for tightness and it came out ok. I'll throw some photos and videos, maybe they will be useful to someone. The head had a lot of pits and replacing the seals themselves did not help, planning it or new one could only fix the problem.
Thank you for your interest and best regards.