Since diesel with an increased biofuel content has been coming out of the petrol pumps, the number of engine failures has also increased. Not that boat engines are particularly picky - on the contrary: the often decades-old technology generally runs on any diesel-like liquid as long as it is free of solids. This is precisely where the problem lies: months often pass between refuelling stops. Time enough to allow the water content of the fuel to rise and create optimum conditions for bacterial growth. The tiny blackheads decompose the diesel and form colonies. The result ranges from tarry sludge to structures resembling wet cotton wool, which can block pipes, filters and the injection system.
Liqui Moly's Marine Diesel Protection is designed to prevent the growth of fungi and bacteria and extend the shelf life of the fuel. The additive is the successor to the tried-and-tested Grotamar 82, which has no longer been freely available for sale since 1 December 2018 due to the tightening of the EU Chemicals Regulation. Marine Diesel Schutz has a formulation adapted to the current legal situation and can also be purchased and used by normal owners. The 500-millilitre container costs around 22 euros and is sufficient for 100 to 500 litres, depending on the dosage. In addition to its antibacterial effect, the additive is also said to increase the cetane number of the fuel and thus improve the starting behaviour of the engine.
Further information is available at: www.gotthardt-yacht.de or www.liqui-moly.de.
Hauke Schmidt
Test & Technology editor
