I have found heavy leak of engine oil into the radiator of my 1996 Mercedes Benz (odometer 150000 mile). The workshop found the oil cooler pump damaged but we could not find a new one in the area. He suggested to run the car without it (temperature was around 70 F).
He informed me that he cleaned the passage of the coolant in the engine but I should expect some oil in the radiator for three days after cleaning and I can remove it by opening the cap and use some tissue to remove it. I used the tissue to remove the oil daily for about two weeks, then I gave up and I removed the oil weekly instead of daily.
After about three months from cleaning (after about 3500 miles), I discovered radiator coolant leakage. I checked the car in the same workshop. They found the leak from the water pump and the bottom of the radiator. My intuition says that the leak is due to the oil in the coolant system. They say that the oil in the coolant system is not the cause. Can you please tell if there is a cause and effect situation here and should I ask them to replace the hoses or just clean them.