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The fuel sold for diesel engines is changing as sulphur content and distillation range are reduced. In addition, alternative fuels are increasingly available from vegetable oil sources. Diesel fuel injection equipment has been optimised to operate with conventional fuel from mineral oil sources and the several designs available today rely on the fuel to lubricate the highly-stressed pumping mechanisms, and the other rolling and sliding conjunctions. Throughout the design range sealing at high pressures relies on close tolerance parts fitting together with very small clearances; such seals are highly sensitive to changes in fuel properties. This paper describes the endurance test by which Lucas Diesel Systems has evaluated the fuel tolerance of rotary distributor fuel injection pumps, and reports the results on 10 test fuels. Operating experience in-house and field test experiences are summarised.

The development of emission regulation proposals for off-highway engines presented a significant challenge to the design of the fuel injection systems. The DP200 range of pumps was evolved from the DPA to meet this need. It incorporates a number of enhancements that will enable emissions compliance. The paper will describe the operation of the new pump systems and show the results of their use on engines. Future evolution of the pump to meet the next round of emissions control and the use of electronics in off-highway markets will be discussed.

This paper describes the rationale that led to the development of the design principles of a full authority electrohydraulic engine valve control system that gives complete control over all valve motion parameters. The evolution of the system's design by use of computer simulation is described together with the operating principle and simulated performance of the final system. Consideration is given to the benefits of combining the system with a high pressure common rail fuel injection system for application to a diesel engine, which leads to an analysis of the advantage that such a system could give in the final application. While the system was intended initially for a diesel engine application, many of the comments apply equally to spark ignition engines.

The paper describes the new features being introduced to the Lucas CAV rotary fuel injection pump product range to meet current market demands. The introduction of an external means of setting the maximum fuel on the traditional rotary pump forms the basis of the new design described in the paper, which also gives the options of excess fuel, boost and torque control. Demands from the diesel engine designer will continue to advance with the advent of increasingly severe emissions legislation. The paper describes future developments to optimise fuel metering and injection timing controls by employing microprocessors to control a rotary distributor pump electronically.