What corrective action can reduce excessive carbon build-up around fuel injector nozzle holes in a large diesel engine?

Increasing the injector cooling water temperature can effectively reduce excessive carbon build-up around fuel injector nozzle holes in a large diesel engine. When the cooling water temperature is increased, it helps to maintain optimal operating conditions within the injector. This higher temperature can aid in ensuring that fuel is vaporized adequately before it enters the combustion chamber, promoting more complete combustion.

When combustion is more complete, it generates less soot and carbon, which are primary contributors to carbon build-up around the injector nozzle. By managing the thermal dynamics of the injector through increased cooling water temperature, the injector can operate more efficiently, leading to reduced deposits.

In contrast, other options may either not effectively address carbon build-up or could exacerbate the issue. For instance, increasing fuel injection pressure generally enhances atomization but can sometimes lead to incomplete combustion if not appropriately balanced with other factors. Similarly, raising fuel preheat temperature may help in certain conditions, but improper management can also lead to higher emissions and potential damage. Decreasing the load limit on the governor could potentially cause the engine to operate less efficiently, which may not resolve the carbon build-up issue effectively.