I try to keep the fuel tank on our Oceanis 37 full or near to full for obvious reasons but recently after a prolonged period of motoring I noticed that the fuel gauge was giving a misleading reading of tank half-full when by my calculation (using an established fuel consumption rate of 2.5 litres per hour at 2500 rpm) we should have used around 100 litres from our 130 litre capacity tank.
If the tank gauge reading was correct then only 65 litres of fuel had been consumed but this was subsequently proven to be incorrect when circa. 100 litres of fuel were required to refill the tank on refuelling.
I am presuming that the tank gauge is either faulty or is reading non-linearly. Has anyone else had the same experience?