MTC Preventive Maintenance Procedures 3

Question 1

When performing PM on a marine battery bank, what voltage reading on a fully charged 12V flooded lead-acid battery indicates acceptable state of charge?

Accepted Answer

12.6–12.8 V

Answer

11.5–11.8 V

Answer

13.5–14.0 V

Answer

10.8–11.2 V

Question 2

A PM checklist calls for inspecting the marine AC generator's drive belt. Which finding requires immediate replacement?

Accepted Answer

Belt shows surface glazing, cracking, or fraying

Answer

Belt has been in service for 12 months

Answer

Belt deflects slightly when pressed

Answer

Belt is the original equipment manufacturer part

Question 3

During a PM inspection of a marine vessel's through-hull fittings, what condition should prompt immediate haul-out and repair?

Accepted Answer

Dezincification (pinkish, porous appearance) or visible cracking of the fitting

Answer

Minor surface discoloration from algae

Answer

Fitting is the original bronze material

Answer

Fitting is located below the waterline

Question 4

What is the correct method to test a marine bilge pump's automatic float switch during PM?

Accepted Answer

Manually lift the float switch while observing pump activation

Answer

Fill the bilge completely with water and wait

Answer

Disconnect the pump and test with a multimeter only

Answer

Run the vessel at full throttle for 30 minutes

Question 5

When topping off a marine diesel day tank as part of a PM procedure, what is the correct reason to leave an air gap at the top of the tank?

Accepted Answer

To allow fuel to expand with temperature changes and prevent overflow

Answer

To reduce the weight of fuel carried

Answer

To improve fuel atomization in injectors

Answer

To allow air to mix with fuel for better combustion

Question 6

A PM schedule requires inspecting marine engine mounts. Which symptom most strongly suggests engine mounts need replacement?

Accepted Answer

Excessive vibration transmitted to the hull or visible rubber deterioration

Answer

Engine runs at normal RPM

Answer

Engine starts easily on the first crank

Answer

Oil pressure within normal range

Question 7

What is the purpose of winterizing a freshwater cooling system with propylene glycol antifreeze rather than ethylene glycol?

Accepted Answer

Propylene glycol is less toxic if it enters the bilge or waterways

Answer

Propylene glycol provides better freeze protection below -60°F

Answer

Propylene glycol is cheaper and easier to find

Answer

Propylene glycol improves corrosion protection in aluminum engines