Hello all.
The car has been leaking coolant for a while now, not the HG, suprise suprise, but somewhere else. Yesterday the leak went from "a bit annoying, and having to top up every week", to major leak. I can see that it's coming from the area with arrows on the pictures below. The car has a DEFA system on it, and I'm wondering if the leaky part is a original part or something from the Defa system?

Looks like a water to oil cooler?

Don't know what has happened, but the leak seem to have stopped(?) Perhaps some dirt from the system has sealed it from the inside? Had the car on a ramp an hour ago, it was indeed a part of the Defa warm up system.

On a side note, the coolant had a lot of "gunk" and dirt in it. Don't think it's oil, as there was no "oily" surface in the tank.