And the trend is rising: in the ninth year since the mineral oil companies started adding green components to diesel fuel, more and more rescue missions are being reported due to engine failures. The DGzRS, for example, reports on its missions caused by engine failures on pleasure craft: In 2014, the rescuers had to tow 437 boats. In 2007, the figure was only 286.
The problem with biodiesel, which is produced for cars and lorries that have a comparatively high throughput: The added biogenic components turn into slime and bacterial cultures in the yacht tanks over time, which can ultimately clog the fuel system. In addition, the fuel cannot be stored; the diesel should be used up after three months if possible. On board, however, consumption is relatively low - so diesel can be stored for longer in large tanks. Like the fuel from the previous season, for example, which was not used in the winter and is outdated in the spring. Then, at the start of the season, the old petrol is used again.
Added biocides help against bacteria, but so far no additive protects against the short shelf life of biofuel. Read in YACHT 22/2015 how to get an affected fuel system clean again and how to avoid the problem altogether. The magazine will be available from newsagents from 21 October.
Hauke Schmidt
Test & Technology editor
