Propulsion:

Arkyla is equipped with the 75hp turbo-charged Yanmar 4JH4-TE diesel engine with KM4A2 gearbox.

Drive is provided by a Flexofold 3-blade folding propeller equipped with an Ambassador Marine rope stripper.

Fuel System

Fuel is stored with a relatively inaccessible keel-located 360-litre fuel tank.  With recent changes to UK and EU regulations on the amount of biofuel that can now be added to petrol and diesel, there is a real risk of diesel bug in marine engines where fuel may be stored in tanks much longer than is the case for road vehicles.  With this in mind, we have engineered a 3-step plan to help maintain the integrity of our fuel onboard.

Step 1 is to always add a fuel additive when filling the tank; we use Marine 16 Diesel Fuel complete.

Theoretical fuel consumption
Diesel Dipper and dual fuel filters

Step 2 is the installation of a Marine 16 'Diesel Dipper'.  The Diesel Dipper works independently from the engine fuel feed system and is designed to suck small amounts of fuel from the very bottom of the tank below the outflow pipe; any water, bug or other contaminants are then separated into a chamber (to be removed from the system) and clean fuel returned to the tank.

Step 3 mitigates in case of contamination; we have replaced the original Delphi primary fuel filter with a dual 'Racor type' system.  If a blockage occurs, then the flow of fuel to the engine can be maintained by the simple flick of a switch without need to prime or bleed the system.  This is important for us as access to the engine is beneath the folding table of the upper deck saloon; working in this space in a rough seaway could be dangerous, but access to the filter switches can be made simply through an inspection lid.