The traditional cold start method for direct-injected, charge air cooled diesel engines for trucks, by use of excess fuel normally means a great deal of white smoke and hydrocarbon emissions. Today this is no longer acceptable.
This paper describes the system used by Volvo to overcome these problems. The design, location and output of starting heaters and the automatic control system are presented, including ambient temperature dependent preheating and afterheating time relays. There is also a description of the design and function of the patented Volvo exhaust pressure governor, which is a combination of a device for warming up the engine by means of a synthetic load and an exhaust brake.
This cold start method is described step-by-step, and compared to the traditional method. Advantages and disadvantages in terms of energy consumption and minimum temperature limits are also discussed. Finally, the paper notes that Volvo has had this type of system in production since 1973, and that it is now standard equipment on all Volvo trucks.
