BoatHowTo · video

What this video covers

Nigel Calder advises against filling diesel fuel tanks before an extended layup, citing the degradation of modern fuels containing bio-content. Instead, he recommends burning off existing fuel to leave the tank nearly empty during storage. When refuelling for the next season, he suggests adding a biocide like Fuel Right early in the process to ensure thorough mixing. Calder dismisses fuel polishing as a primary solution, arguing that it fails to address the root cause of contaminated fuel: a dirty tank. He identifies cleaning the fuel tank as the single most important maintenance task for marine diesel engines. If a tank lacks adequate access, he suggests installing a sealable inspection port, such as those manufactured by Vetus, to allow for manual cleaning and future monitoring. Proper tank hygiene and diligent fuel filter maintenance eliminate the need for external polishing systems.

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