Feather Diesel Services Ltd. Steve Smith - MD Specialist repairs of Diesel fuel injection equipment. Established 1954.

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2 Feather Diesel Services Ltd Steve Smith - MD Specialist repairs of Diesel fuel injection equipment. Established 1954.

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4 Diesel Fuel Injection Modern Diesel engines have to meet stringent emissions regulations. The fuel injection equipment that control the timing and flow of Diesel to the combustion chambers are critical to the performance, emissions and fuel consumption of a Diesel vehicle. Diesel Fuel Injection technology has evolved to meet these emissions regulations.

5 Diesel Fuel Injection Past now historic Mechanical fuelling physically set with mechanical stops. Operating pressure up to 900 bar. Present now past EDC fuelling controlled by vehicle ECU which allows adjustments. Operating pressure up to 1150 bar. Future now present VP and Common Rail greater control on fuel delivery and timing. Operating pressure 1350 to 2000 bar.

6 Reducing Emissions Technology Delphi Automotive Common Rail Conclusion Questions

7 Evolution of Diesel systems. Delphi Automotive Common Rail Conclusion Questions

8 Reducing Emissions Technology Delphi Automotive Common Rail Conclusion Questions

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10 Low-pressure fuel circuit with Electric Fuel-pump The pre-supply pump is an intank electric fuel-pump and also performs the safety shut-off. 1 = Electric fuel-pump 2 = Fuel filter 3 = Overflow valve 4 = Return-fuel accumulator 5 = High-pressure pump CP1 6 = High-pressure regulation valve 7 = Rail-pressure sensor 8 = Rail (distribution duct) 9 = Injectors 10 = EDC 15 C control-unit 11 = Fuel-temperature sensor 12 = Other sensors

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12 Low-pressure fuel circuit with Electric Fuel-pump 1 = Driveshaft 2 = Eccentric cam 3 = Pump element 4 = Intake valve 5 = Element-shutdown valve 6 = Outlet valve 7 = Seal 8 = High-pressure connection to rail 9 = Pressure-control valve 10 = Ball valve 11 = Fuel return 12 = Fuel intake 13 = Throttle valve (safety valve) 14 = Low-pressure passage Element-shutdown active, 12 Volt.

13 CP1 Principle of Operation The rotation of the driveshaft produces an eccentric motion of the polygon ring, thus creating a pumping action to the plungers 1 = Eccentric driveshaft 2 = Polygon ring (cam) 3 = Pumping element 4 = Inlet valve 5 = Outlet valve 6 = Inlet

14 CP1 Principle of Operation The filter on the control side must not be touched because it will become blocked and impair the operation of the regulating valve 5 micron filter

15 Electro-magnetic control 1 = Fuel return 2 = Valve spring 3 = Electromagnet 4 = High-pressure connection 5 = Valve armature 6 = Valve ball 7 = Output throttle 8 = Control chamber 9 = Inlet throttle 10 = Valve control-plunger 11 = Nozzle needle 12 = Injector nozzle a = Injector closed b = Injector opened (injection)

16 Common Rail Delphi Automotive Common Rail Conclusion Questions Injection cycle less than 100 microseconds between injections Design enables: Pre-injection Post-injection Currently developing a system with seven separate fuel injections per cycle!

17 Injector Assembly High Pressure Gallery Electrical Connect or Diaphragm Hydraulic Damper Overflow Connector Nozzle Needle Piezo Assembly Servo Control Valve Assembly Inlet/Outlet and Bypass Assembly

18 Injector Actuator Delphi Automotive Common Rail Conclusion Inlet orifice(ino) Dia 0.25mm Questions Nozzle Path Orifice Dia 1.00 mm By Pass Orifice Dia 0.2mm

19 Actuator tolerances Delphi Automotive Common Rail Conclusion Actuator lift mm Questions Bore Dia 0.40 mm Operating clearance mm Bore Dia mm

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21 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 EN14214 provides the minimum requirements for FAME quality whether used as pure FAME or as a blend component. FAME may be currently blended in quantities of up to 5% in European diesel fuel according to the EN590 specification. In order to reduce the risk of premature failure of the fuel system FAME must conform to EN Increasing biodiesel production capacities in the EU have enabled legislative authorities to consider increasing the maximum biodiesel blending level from 5 to 10 percent. Activities are ongoing to standardize and validate biodiesel blends with up to 10 percent biodiesel (B10) in the EU. The FIE industry considers it as essential to maintain the fuel stability level of EU-B5 (IP 20h acc. to modified EN14112) also for future B10 blends. In any case an approval of B10 requires positive validation of B10 specific issues additionally.

22 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 To date, experience in Europe has been mainly associated with the methyl esters of rapeseed oil. Whether or not the service experience with these fuels will apply/extend to all FAMES (like those derived from soybean, tallow and used frying oil) has yet to be determined. FIE Manufacturers Concerns: FAMEs are derived from a wide range of base stocks, resulting in a similarly wide range of finished fuel characteristics. Amongst the concerns of the FIE manufacturers are the following fuel characteristics: free methanol - water free glycerine mono, di- and triglycerides free fatty acids total solid Impurity level alkali/alkaline earth metals oxidation stability

23 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 All FAMES are less stable than mineral oil derived fuels. FAMEs are readily "bio-degradable" in the event of accidental spillage or leakage, which is claimed to be a marketing advantage. On the other hand, the reduced thermal oxidative stability is of major concern to the FIE manufacturers, as the products of fuel ageing can be potentially harmful to the fuel system. Tests have shown that fuel deterioration can take place in the fuel supply chain and in the vehicle fuel system. Fuel ageing is accelerated in the presence of heat, oxygen, water, metal ions and other impurities. The products of oxidative ageing have been shown to be, corrosive (e.g. organic acids like formic and acetic acids and acids of higher molecular weight). Polymerisation products are also formed and can drop out.

24 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 The required quality of the FAME fuel is defined in European standard EN14214, which covers relevant impurities and tramp chemicals from the processing, Suppliers of FAME fuels must be able to demonstrate compliance to this standard at the filling station. There are several risks associated with possible supply chains. For the FIE manufacturers a key property of any FAME fuel is the resistance to oxidation. Aged or poor quality FAME contains organic acids like formic and acetic acids and acids of higher molecular weight as well as polymerization products which attack many components, drastically reducing the service life of the FIE. A list of issues which have been witnessed in service is detailed in the attachment to this document.

25 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 The FIE manufacturers can accept no legal liability for failure attributable to operating their products with fuels for which the products were not designed, and no warranties or representations are made as to the possible effects of running these products with such fuels. Non-compliance of the fuel to standards agreed by the FIE manufacturers, whether being evident by appearance of the known degradation products of these fuels, or their known effects within the fuel injection equipment, (see attached list of known issues) will render the FIE Manufacturers' guarantee null & void,

26 Diesel Fuel Injection Equipment Manufacturers Common Position Statement on Fatty Acid Methyl Ester (FAME) Fuels as a Replacement or Extender for Diesel Fuels January 2007 Fuel Injection Equipment Potential Problems with FAME, (Non-exhaustive list) See Hand out!!!!

27 Diesel Fuel Injection Equipment Biodiesel is known to break down deposits of residue in fuel lines where petrodiesel has been used leading to filter plugging. Biodiesel may contain small but problematic quantities of water.(due to persistence of mono and diglycerides which act as an emulsifier allowing water to mix with biodeisel.) Water can be residual amounts from processing or from storage tank condensation.

28 Diesel Fuel Injection Equipment Water related problems include: Reduced heat of combustion increased smoke lower power and hard starting. Corrosion of fuel injection equipment. Water and microbes cause filters to rot pass larger particles to FIE. Water content causes premature ice crystallisation and fuel gelling. Water accelerates growth of microbe colonies. Water can cause piston crown pitting.

29 Diesel Fuel Injection Equipment Review Damage caused by unsuitable fuels.

30 Thank You Thank you for your valuable time. Any other questions. Special thanks to Robert Bosch and Delphi.

31 THE COMPLETE SOLUTION