Vehicle Inspection & Maintenance Flashcards

Before launching a trailered boat, what is the single most important electrical connection to disconnect before submerging the trailer?

Answer: The trailer's running light wiring connector

Disconnecting the trailer wiring harness before the trailer enters the water prevents shorting of the lights and protects bulbs and wiring from thermal shock when hot bulbs contact cold water.

A visual inspection of your outboard motor's lower unit shows oil leaking from the gear case drain plug area. What is the most likely cause?

Answer: A failed seal is allowing gear lube to escape, and water may be entering the gear case

A leaking lower unit gear case seal allows expensive gear lube to escape and allows water to enter, which can destroy the gears and bearings if not addressed.

What does the 'pre-departure checklist' item 'check the drain plug' refer to, and why is it critical?

Answer: The hull drain plug must be installed before launching to prevent the boat from taking on water and sinking

Failing to install the hull transom drain plug before launching allows water to flood the bilge rapidly — a common cause of dock-area sinkings.

When inspecting dock lines and mooring lines on your vessel, what condition makes a line unsafe for continued use?

Answer: Lines with significant chafing, fraying, stiffness from UV damage, or reduced diameter sections

Chafing, fraying, UV degradation (stiffness, color fading), and necking down are signs of reduced breaking strength that could cause line failure when you need it most.

What is the correct way to store a portable fuel tank on a recreational boat?

Answer: In an exterior, ventilated location away from ignition sources, not in an enclosed compartment

Portable fuel tanks must be stored in a ventilated, exterior location away from ignition sources because fuel vapors can accumulate and explode in enclosed spaces.

What should you do if your boat's engine does not start and you detect a strong smell of gasoline when you open the engine hatch?

Answer: Keep the hatch open, run the blower for at least four minutes, then check for the source of the leak before attempting a restart

Running the blower for at least four minutes evacuates explosive fuel vapors from the bilge; only then should you investigate the source of the fuel smell before attempting to restart.

How does salt water affect stainless steel hardware on a boat differently from freshwater, and what maintenance does this require?

Answer: Salt water deposits chlorides that can cause crevice and pitting corrosion in stainless steel, requiring regular rinsing and inspection

Chloride ions in salt water penetrate the protective oxide layer on stainless steel and cause crevice corrosion, especially under fittings; regular freshwater rinsing and periodic inspection are required.