AGR Cleaning: Flush After 100,000 km?

Hello fellow enthusiasts,

My engine has now reached 102,000 km with the EGR valve being mistreated, yes, yes, I know that's not how it's supposed to be done! But the engine in my agricultural machine isn't one of the most accessible engines (with fuel injection lines and other stuff everywhere, it's not a pleasure to work on). Anyway, the EGR valve is now broken, and I'm wondering if it would be worthwhile to clean the oil cooler + hoses, as well as the intake manifold for both cylinder heads, in some way, to remove the oil residue. The benefit from cleaning the hoses and the intake manifold might not be noticeable or measurable, but I think it could potentially make a difference with the oil cooler.
Because a thick layer between the compressed air and the cooling fins doesn't necessarily result in better efficiency. What do you think about that? Is the effort worthwhile, considering the benefits?

Hi Marco,

Please take a look at the TDI diagrams. The air comes from the air filter, goes to the turbocharger, then through the hoses to the intercooler (charge air cooler), then to the EGR valve, and finally to the intake manifold (very roughly simplified, and omitting some components like the mass airflow sensor).

Anything located before the AGR valve will not be affected by its "sludge" because only air flows through that area. The only things that might be slightly oily are the hoses and the coolant, but that's normal unless your turbo is leaking a large amount of oil.

According to reports from the forum, cleaning the intake manifold (or manifolds in your case) actually makes a significant difference, as it removes quite thick layers of deposits.

Best regards,

Jan.

Hi Jan,

According to the diagrams, it should be like this. However, my engine is completely coated in oil sludge. It can't be coming from the turbo because the pipes behind the turbo are relatively clean. It's probably the EGR valve, otherwise I wouldn't be asking these questions.

Hi,

"Then perhaps the LLK (likely the oil cooler) is the point where the oil mist settles - there's probably enough surface area on the fins for that to happen. It couldn't be coming from the AGR (likely the exhaust gas recirculation system), because the dirt would have to travel over half a meter against the airflow of the turbo."

Best regards,

Jan.

Hi,

Then the dirt would have to overcome a distance of more than half a meter against the airflow of the turbo.

Hello Jan,

You're right, it's probably unlikely.
Do the temperatures in the low-temperature cooling system (LLK) provide sufficient drying to remove the oil mist?
And most importantly, how and with what means can I get this item clean again?