GENERAL SERVICE INFORMATION Diesel Fuel 12/05 Precautions and concerns regarding the use of bio-fuels: Diesel Fuel Lines Shown is a typical installation of a boat fuel system. Fuel supply (Figure 3-10, (2)) and return (Figure 3-10, (4)) lines connect to fittings at the engine. Biodiesel fuels have a higher content of methyl-esters, which may deteriorate certain metal, rubber and plastic components of the fuel system. The customer and / or boat builder are responsible to verify the usage of biodiesel compatible components on the vessel fuel supply and return systems. Figure 3-10 (2) (1) (4) Free water in biodiesel may result in plugging of fuel filters and increased bacterial growth.
(5) High viscosity at low temperatures may result in fuel delivery problems, injection pump seizures and poor injection nozzle spray atomization. (3) (6) (8) (7) Biodiesel may have adverse effects on some elastomers (seal materials) and may result in fuel leakage and dilution of the engine lubricating oil. 0003638 Figure 3-10 Even biodiesel fuels that comply with a suitable standard as delivered, will require additional care and attention to maintain the quality of the fuel in the equipment or other fuel tanks. It is important to maintain a supply of clean, fresh fuel. Regular flushing of the fuel system, and / or fuel storage containers, may be necessary.
1 – Optional Boat Builder Installed Fuel Filter / Water Separator* 2 – To Fuel Feed Pump 3 – Less than 500 mm (19.68 in.) 4 – Fuel Return Line 5 – Fuel Tank 6 – Fuel Tank Drain Cock 7 – 20 to 30 mm (0.75 to 1.125 in.) 8 – Fuel Shutoff Valve The use of biodiesel fuels that do not comply with the standards as agreed to by the diesel engine manufacturers and the diesel fuel injection equipment manufacturers, or biodiesel fuels that have degraded as per the precautions and concerns above, may affect the warranty coverage of the engine. *Note:Yanmar supplies a water separating pre-filter for mounting by the installer. The engine is also equipped with an on-engine fine filter. NOTICE:
The fuel supply line between the fuel tank and engine must be a minimum diameter of 8 mm (0.315 in.). Install a drain cock (Figure 3-10, (6)) at the bottom of the fuel tank to remove water and contaminants. Boat fuel supply system restriction must not exceed 1000 mmAq (39.37 in.Aq). Boat fuel return system restriction must not exceed 200 mmAq (7.87 in.Aq). © 2009 Yanmar Marine International BY Service Manual 3-13