Calibrating oil is the translation from Dutch to English. What you want is calibration fluid. Diesel fuel is hygroscopic and over time will absorb a bit of water. If it freezes much over winter that can have a detrimental effect on the injection pump and injectors. Calibration fluid is not hygroscopic and thus wont absorb water. It is pricy but you can buy a quart (or gallon) from any shop that does actual injection pump repair.
Connect the fuel line from the lift pump directly to the container with calibration fluid and start the engine. One quart is more than enough to protect an engine's injection system from water damage.
Marine Diesel Engine Vendor