I am working on a buddies sportwagen. At the moment it is getting its second timing belt, replacing a failed DMF, the DPF, and EGR cooler. IT had some emissions codes and he wanted to just replace the cooler and DPF due to mileage.
Anyhow, he had stopped driving it recently because he noticed that the coolant reservoir was pretty nasty inside. I suggested that the oil cooler or trans cooler were likely culprits, and since he wants to car to go another 250k he decided to replace them both while doing all of this other work. Only issue is that Once I got everything taken apart I did a redneck pressure test on the coolers. I submerged the oil portion of the oil cooler in water and pressurized the coolant side. No bubbles. Likewise with the trans cooler I submerged the coolant hose connections and pressurized the trans side of the cooler. No bubbles out of the coolant ports.
So now I am at a bit of a loss. Is there anywhere else for oil and coolant to mix besides head gasket?
I cut open the reservoir since It was leaking and being replaced to see what the inside looked like
I also posted in the Jetta specific section
Anyhow, he had stopped driving it recently because he noticed that the coolant reservoir was pretty nasty inside. I suggested that the oil cooler or trans cooler were likely culprits, and since he wants to car to go another 250k he decided to replace them both while doing all of this other work. Only issue is that Once I got everything taken apart I did a redneck pressure test on the coolers. I submerged the oil portion of the oil cooler in water and pressurized the coolant side. No bubbles. Likewise with the trans cooler I submerged the coolant hose connections and pressurized the trans side of the cooler. No bubbles out of the coolant ports.
So now I am at a bit of a loss. Is there anywhere else for oil and coolant to mix besides head gasket?
I cut open the reservoir since It was leaking and being replaced to see what the inside looked like
I also posted in the Jetta specific section
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