Hi Vitaloni, Oil from the header tank slowly seeps into the engine causing 'wet sumping', if your car has been standing awhile drain the oil out of the sump and simply pour it back into the header tank. The oil level in the tank will give you a clue. Foolishly I tried to start the car after Covid lockdown, it had wet sumped and blew the rear crank oil seal, engine out job and ££££
