Question 4 CEL01 - Chief Engineer - Limited

The Correct Answer is B **Explanation of Option B (Correct Action):** Option B, "Make certain that the hydraulic reservoir is filled to the proper level," is the correct first action because a hydraulic pump cannot develop pressure if it is starved of fluid. Since the electric motor is confirmed to be operating properly (meaning the pump shaft is turning), the lack of pressure development indicates a failure in the fluid supply circuit. The most common and easiest-to-remedy cause of zero output pressure is a low fluid level in the reservoir, causing the pump to run dry or cavitate (suck air). Checking the fluid level is the logical first step before investigating internal pump failures or complex electrical issues. **Explanation of Incorrect Options:** * **A) Check for full voltage supply to the electric motor:** The prompt states the electric drive motor is operating properly. While low voltage can cause inefficiency, if the motor is running, the voltage is sufficient to turn the pump shaft. Low voltage would not typically result in *zero* pressure unless the motor completely stalled, which contradicts the premise. * **C) Check the electric motor for an open overload relay contact:** If the overload relay contact were open, the electric motor would not be running at all. Since the motor is confirmed to be operating properly, this option is irrelevant. * **D) Inspect the disc brake on the electric motor for proper operation:** If the disc brake were improperly engaged, it would either prevent the motor from turning, or cause the motor to trip an overload. Since the motor is operating properly, it implies the motor shaft (and thus the pump shaft) is turning. Therefore, the brake is not the cause of the zero pressure output. Zero pressure is a fluid issue, not a driving issue under these conditions.