What is a common problem when starting a diesel engine?

In the context of starting a diesel engine, retarded injection timing is a significant problem that can hinder starting performance. Diesel engines rely on precise timing for fuel injection to ensure optimal combustion. When the injection timing is retarded, or happens later than the ideal point, the fuel may not ignite effectively. This delay can result in incomplete combustion, leading to hard starting or failure to start altogether. A diesel engine functions based on high compression, and any disruption in the timing of fuel delivery can drastically impact its ability to start smoothly.

While overheating, inadequate fuel supply, and excessive airflow can also present issues during engine operation, they are not typically the primary concerns during the starting phase. Overheating usually occurs due to prolonged operation rather than being a direct cause of starting difficulties. An inadequate fuel supply can hinder operation but is not confined to the starting procedure itself. Excessive airflow, while it can affect combustion, is generally not a decisive factor in starting a diesel engine compared to the crucial role of injection timing. Thus, understanding the significance of injection timing, especially during the engine's start-up, underscores why it is a common problem in this context.