Man they cook with oil to cool them I can't picture oil free not burning up. They glow red hot with cooling and is why you have to allow them to cool down before shut off.
Please either give a link or explain how they don't burn up.
EDIT: are you talking about this water cooled set up? https://www.compturbotechnology.com/3993s-ol
If so you should read the reviews. All negative. They recommend packing them with special grease every 10,000 but most say they never make it that far and the price of repacking them with grease keeps going up.
To achieve anything, you must be prepared to dabble on the boundary of disaster.”
Sir Stirling Moss