Very true regarding the aluminium - steel corrosion. When I once replaced my drysump lines there were none available, so I had them made by an aircraft hydraulics manufacturer. But I had to reuse the fittings, so cutting the stubborn nuts on the cooler was no option. Heat alone is of little help, because the male threaded portion on the aluminium oil cooler expands significantly more, than the steel nut, what locks the connection even more. I worked with heat on the nut and cooling spray on the oil cooler. After a few hot / cold cycles the nut came loose without any damage neither on the oil cooler nor on the nut. Best Regards Martin
