EETC - Equipment & Engine Training Council Mechanical Systems and Components Questions and Answers

Question 1

A technician is servicing a piece of equipment, such as a walk-behind trowel, that requires a low output speed and high torque from the engine.
Which of the following mechanical systems is used to achieve this?

Accepted Answer

A gear reduction system

Answer

A flywheel with extra counterweights

Answer

An advanced timing system

Answer

A high-velocity cooling fan

Question 2

What is the primary function of the lobes on a camshaft in a four-stroke engine?

Accepted Answer

To actuate the intake and exhaust valves at the correct time

Answer

To balance the crankshaft's rotation

Answer

To splash lubricate the cylinder walls

Answer

To create the spark for ignition

Question 3

A customer brings in a single-cylinder engine that is vibrating excessively during operation. The technician has already confirmed the external mounting bolts are secure and the attached equipment (e.g., blade, pump) is balanced and undamaged. Which internal component is most likely responsible for minimizing this type of vibration?

Accepted Answer

The crankshaft counterweights

Answer

The piston rings

Answer

The valve springs

Answer

The oil pump

Question 4

Which type of bearing is best suited for applications with high radial loads in a compact space, such as in the connecting rod or as crankshaft main bearings in some small engines?

Accepted Answer

Needle roller bearings

Answer

Thrust ball bearings

Answer

Magnetic bearings

Answer

Plain sleeve bearings without rolling elements

Question 5

A technician is having difficulty pulling the starter rope on a high-compression four-stroke engine. The resistance is extremely high. Which mechanism is designed to make starting easier by slightly opening a valve during the initial part of the compression stroke?

Accepted Answer

An automatic compression release (ACR)

Answer

A governor system

Answer

A flywheel brake

Answer

A rewind spring assist

Question 6

When diagnosing the cause of a bent crankshaft on a lawnmower, which of the following is the most common cause?

Accepted Answer

Impact with an immovable object like a rock or tree stump

Answer

Using the wrong viscosity oil

Answer

A sheared flywheel key

Answer

Over-tightening the spark plug