4-Stroke
Why is the compression stroke critical for combustion efficiency?
It increases pressure and temperature for better fuel ignition
What is the function of transfer ports in a 2-stroke engine?
They move the air-fuel mixture from the crankcase into the combustion chamber
What effect does pollen buildup have on engine performance?
It can clog air filters and restrict airflow
Why should rotating parts be fully stopped before inspection?
To prevent entanglement or injury
What diagnostic tool would you use to test ignition system performance?
Spark tester
What mechanical component ensures proper synchronization between crankshaft and camshaft?
Timing Gear
Why do 2-stroke engines require a fuel-oil mix instead of having a separate oil reservoir like 4-stroke engines?
Because 2-stroke engines rely on the oil mixed in fuel to lubricate the piston and crankcase during operation
Why is it recommended to inspect fuel lines in spring?
Cold weather can cause cracking or brittleness
Why is proper disposal of used engine oil critical?
It prevents environmental contamination and legal violations
How does a feeler gauge ensure proper engine operation?
It measures precise gaps like valve lap or spark plug gap
How does incorrect valve lap affect engine performance?
Can cause poor compression, noise, overheating, or valve damage
What is the function of reed valves in some 2-stroke engines?
They control airflow into the crankcase and prevent backflow
During the spring equinox, what is unique about the length of day and night?
They are approximately equal worldwide
What is the primary hazard of running an engine in an enclosed space?
Carbon monoxide poisoning
What does a compression tester reveal about engine condition?
Cylinder sealing ability and internal wear
What engine damage can result from a failed lubrication system in a 4-stroke engine?
Seized piston, scored cylinder walls, or moving part failure
Why are 2-stroke engines generally less fuel-efficient than 4-strokes?
Some unburned fuel escapes during scavenging
Why is soil temperature more important than air temperature when determining the ideal time for spring planting?
Because seed germination and root development depend on soil temperature, not air temperature
What is the risk of over-tightening fasteners on aluminum engine components?
Thread stripping or component cracking
What specialized gardening tool is designed to remove deep-rooted weeds without disturbing surrounding plants?
A weeding fork
How does a worn or damaged piston ring affect engine performance in a 4-stroke engine?
It reduces compression, allowing blow-by, which leads to power loss and increased oil consumption
How does crankcase compression contribute to engine operation in a 2-stroke?
It pre-compresses the air-fuel mixture before transfer to the cylinder
What is the primary function of a valve spring in a 4-stroke engine?
To return the valve to the closed position and maintain proper valve seating
Who is the least safe student in the class?
NO ONE!... right?
What is the primary purpose of a torque wrench when assembling small engine components?
To apply a precise amount of force to bolts or nuts, preventing overtightening or under-tightening that could cause damage or failure