Removing engine oil from Coolant?

Hi all. I know there's a thread somewhere about removing oil from coolant, but for the life of me I can't find it.

My problem is I found engine oil in the radiator of one of our tractors prepping it for winter. Pulled the radiator and had it leak checked and they found a leak in the engine oil cooler once it got warm and under pressure. I pulled the T-stat and purged the remaining coolant from the block with air and saw only clean coolant, no oil.

I plan fill with water and flush again...

Removing engine oil from Coolant?

Removing engine oil from Coolant?