MST Study Guide 2026
Everything you need to pass the MST exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 MST Exam Format at a Glance
📚 MST Topics to Study (22)
✍️ Sample MST Questions & Answers
1. What ABYC standard governs the installation of gasoline fuel systems on recreational boats?
ABYC H-24 (Gasoline Fuel Systems) establishes minimum safety standards for fuel tanks, lines, fittings, and ventilation on recreational vessels.
2. What is the maximum distance at which two VHF radios at sea level can typically communicate using line-of-sight propagation?
VHF radio is line-of-sight, and the range between vessels is limited by antenna height above the waterline — typically 20–25 nm vessel-to-vessel at normal antenna heights.
3. When adjusting trim tab position on an outboard, moving the trim tab to port will cause the boat to turn in which direction?
Moving the trim tab to port deflects water flow to the right side of the lower unit, creating a force that steers the stern to port and the bow to starboard.
4. When flushing a saltwater outboard engine after use, what is the correct procedure?
Running the engine with a flush muff circulates fresh water through the entire cooling system to remove salt deposits that cause corrosion and blockage.
5. Water in the outboard gear oil is most commonly caused by what condition?
Water enters the lower unit most often through a failed propeller shaft seal, especially if the prop has hit an obstruction and damaged the seal.
6. Why is it important to inspect the marine engine’s exhaust system?
Inspecting the marine engine’s exhaust system is critical for both engine performance and safety. Blockages, such as carbon buildup, can restrict exhaust flow, reducing engine efficiency and potentially causing overheating. More importantly, leaks in the exhaust system can allow dangerous carbon monoxide fumes to enter the boat's cabin, posing a severe health risk to occupants. Regular checks ensure proper gas expulsion and prevent these hazards.