Preventive Maintenance Procedures Flashcards
7 cards from real MTC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Preventive Maintenance Procedures flashcards as text
During PM, a technician notices the marine engine's freshwater cooling system thermostat opens at 195°F but the engine continues to run at 210°F. What is the most likely cause?
Answer: Partial blockage in the heat exchanger or raw water circuit
A thermostat opening correctly but the engine still overheating points to restricted coolant flow, most commonly a fouled heat exchanger or blocked raw water strainer.
When conducting PM on a vessel's steering system, what is the correct way to check hydraulic steering fluid level?
Answer: Check with steering centered and engine off after bleeding any air
Checking hydraulic fluid with the steering centered and engine off gives an accurate resting level reading and avoids false highs or lows caused by fluid displaced during turns.
A PM inspection of a marine vessel's safety equipment reveals that flare expiration dates have passed. Under USCG regulations, what is the correct course of action?
Answer: Expired flares must be disposed of properly and replaced with current, unexpired USCG-approved signals
USCG regulations require that visual distress signals be current (unexpired); expired flares may be carried as extras but cannot count toward the required complement.
When performing a compression test on a marine diesel engine during PM, which result indicates a worn or broken piston ring?
Answer: One cylinder reads significantly lower than the others, improving after adding oil (wet test)
Low compression that improves with a wet test (adding oil to the cylinder) indicates ring wear because the oil temporarily seals the gap the worn rings cannot close.
What is the recommended torque sequence when re-installing a marine engine cylinder head after PM work?
Answer: Start from the center and work outward in a crossing pattern per OEM spec
Torquing from the center outward in a cross pattern ensures even gasket compression and prevents warping the head.
During PM, a technician inspects a marine vessel's shore power cord and notes the plug is discolored and feels warm after normal use. What is the correct action?
Answer: Replace the shore power cord and inspect the inlet receptacle for damage or corrosion
Heat discoloration in shore power connections indicates high resistance from corrosion or a loose connection, which is a fire hazard requiring immediate replacement and inspection.
What is the standard PM interval for replacing the fuel filter on a four-stroke marine outboard operating in normal conditions?
Answer: Every 100 hours or annually, whichever comes first, per OEM guidelines
Most OEMs recommend fuel filter replacement every 100 hours or annually to prevent contaminants from reaching the carburetor or fuel injection system.