MST MST Marine Fuel Systems

Question 1

What ABYC standard governs the installation of gasoline fuel systems on recreational boats?

Accepted Answer

ABYC H-24

Answer

ABYC H-24 (Gasoline Fuel Systems) establishes minimum safety standards for fuel tanks, lines, fittings, and ventilation on recreational vessels.

Question 2

Why must marine carburetors have a backfire flame arrestor?

Accepted Answer

To prevent engine backfires from igniting fuel vapors in the bilge

Answer

A backfire flame arrestor stops flames from a carburetor backfire from reaching fuel vapors that may have accumulated in the engine compartment or bilge.

Question 3

What is the minimum number of ventilation openings required for a gasoline-powered engine compartment per ABYC standards?

Accepted Answer

At least two — one for intake and one for exhaust

Answer

ABYC requires at least one intake and one exhaust vent to ensure adequate air circulation and dilution of fuel vapors.

Question 4

Which type of fuel hose is required for use below the waterline on a marine fuel system?

Accepted Answer

USCG Type A1 (fire-resistant, non-permeating)

Answer

USCG Type A1 fuel hose is required below the waterline because it is both fire-resistant and non-permeating to prevent vapor diffusion.

Question 5

What is the maximum allowable fuel tank fill rate before vapor lock or overflow becomes a risk in a portable tank system?

Accepted Answer

Fill slowly to allow vapors to escape and stop before fuel spills

Answer

Portable tanks should be filled slowly to allow vapor displacement and stopped before spilling to prevent fire and water pollution violations.

(MST) Marine Service Technician Practice Test

(MST) Marine Service Technician Practice Test

MST MST Marine Fuel Systems