Question 35 DDE01 - Designated Duty Engineer - Unlimited HP

The Correct Answer is D. **Why Option D is Correct:** Option D states: "The oil level detector must be replaced with a new detector if it is found to be defective, since field adjustments are not possible on this type of unit." A "sealed unit" in technical documentation, particularly for sensitive safety devices like low crankcase oil level detectors, generally means the component is designed to be maintenance-free, tamper-proof, and non-adjustable in the field. The seal ensures integrity and reliable operation according to factory specifications. If the unit malfunctions (i.e., fails to alarm when the level is low), the accepted maintenance procedure is replacement with a new, certified, sealed unit. Attempting to break the seal and adjust the internal components compromises the unit's safety rating and reliability, which is unacceptable for critical engine protection systems. **Why Other Options Are Incorrect:** * **A) The oil level detector is adjusted just as if it was an unsealed unit, but the seals must be re-established before placing the unit back into operation.** This is incorrect because the unit is explicitly described as a *sealed unit* designed for non-adjustment. Breaking the seal to adjust it, even if new seals are applied afterward, fundamentally alters the unit's certification and intended design, potentially compromising its reliability. * **B) The oil level detector is adjusted just as if it was an unsealed unit, without regard to any seals associated with the unit.** This is incorrect and highly negligent. Ignoring seals and adjusting a critical, sealed safety device compromises the engine protection system's integrity and is poor maintenance practice. * **C) The oil level detector seals must be broken before adjustments can be made, as long as new seals are established before placing the unit back into operation.** This is incorrect for the same reasons as Option A. The technical definition of a "sealed unit" implies that internal components are inaccessible and non-adjustable by the user or technician. Once the seal is broken, the unit is generally considered defective and must be discarded, not repaired and resealed.