Generator Set Maintenance Flashcards
7 cards from real EGSA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Generator Set Maintenance flashcards as text
When performing a load bank test on a standby generator, what minimum load level is typically recommended to prevent wet stacking?
Answer: 75% of rated capacity
Load bank testing at 75% or more of rated capacity burns off carbon deposits and unburned fuel that cause wet stacking in lightly loaded diesel engines.
Which maintenance task is most critical before storing a generator set for an extended period of more than 6 months?
Answer: Fogging the engine cylinders with preservation oil
Fogging cylinders with preservation oil prevents rust and corrosion on cylinder walls and piston rings during long-term storage.
A generator's voltage regulator is replaced but the output voltage still fluctuates. What is the most likely next component to inspect?
Answer: Alternator brushes and slip rings
Worn or contaminated brushes and slip rings cause irregular contact, producing voltage fluctuation even with a new AVR installed.
What does a rising trend in crankcase pressure readings during routine maintenance indicate?
Answer: Worn piston rings or cylinder liners allowing blow-by
Elevated crankcase pressure indicates combustion gases are bypassing worn piston rings into the crankcase, a sign of internal engine wear.
During a maintenance inspection, technician finds white crystalline deposits around coolant hose fittings. What does this indicate?
Answer: Slow coolant leak allowing deposits to form as coolant evaporates
White crystalline deposits around fittings are a classic sign of a slow coolant leak where the liquid evaporates and leaves mineral residue behind.
What is the recommended method for checking injector spray pattern without removing injectors from the engine?
Answer: Observing exhaust smoke color under controlled load conditions
Exhaust smoke analysis under controlled load provides a practical field assessment of combustion quality and injector performance without disassembly.
When replacing a flexible exhaust coupling on a generator set, what characteristic is most important when selecting the replacement part?
Answer: Matching the original manufacturer's temperature and vibration rating
The replacement coupling must meet or exceed the OEM temperature and vibration specifications to ensure safe and reliable operation.