Two weeks ago I refueled the boat taking photographs along the way.
This photograph below shows the starting point of the refueling with the needle at the 1/4 of a tank mark.
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| At start of refueling |
The next photograph shows the position of the needle after 20 liters of diesel were added to the tank.
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| After 20 liters added |
Then after another 20 liters were added:
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| After another 20 liters added (for a total of 40 liters) |
Then after another 20 liters were added:
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| After another 20 liters added (for a total of 60 liters) |
Even though the gauge was registering full I manage to put in another 7 liters of fuel to get the final reading of the gauge below.
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| After a total of 67 liters added |
This effort provided me with valuable insight into what the needle positions really mean.
Given the empirical finding that the fuel tank has a capacity of 125 liters and that it took 67 liters to take the gauge from 1/4 to full, I now know that a reading of just touching "Empty" represents 35 liters remaining in the tank and 1/4 tank actually represents 58 liters remaining in the tank, rendering it almost half (46%) full. That is not surprising given that even in an automobile the tank float hits bottom with fuel still remaining in the tank, giving rise to the phrase "running on empty".
To make things more fuzzy, the state of the boat in the water affects the reading. The exercise above was performed with Pachuca lying quietly in her pen. In open water either bobbing at an anchorage or worse, under sail with the boat pitching, yawing, and rolling the gauge must be considered to be only a rough approximation of the reality.
