Question 429Motor Plants - Assistant Engineer

The correct answer is D) carefully check for binding in the governor linkage. The governor is responsible for maintaining a constant engine speed, and hunting (fluctuations in speed) indicates an issue with the governor's operation. If changing the oil, flushing the governor, and adjusting the compensation needle valve did not resolve the hunting, the next logical step is to check for any binding or mechanical issues in the governor linkage. Binding in the linkage can prevent the governor from functioning properly and cause the observed hunting behavior. The other options are not the best next steps in this situation. Checking the air intake manifold pressure (A) or calibrating the fuel pump rack settings (B) are not directly related to the governor's operation. Setting the speed droop adjustment to zero (C) may not resolve the issue if the root cause is a mechanical problem in the linkage.