Chapter 1 - Quiz Engine Maintenance PowerPoint slides by Stf/C Harl Porter, SN Marine Electronics 107Harl@sc.rr.com Rear Commander for Electro-Mechanical Systems is R/C Gene Danko, SN

b. Air, fuel, source of ignition. c. Fuel, ignition, lubrication. 1. What three basic things are required for an internal combustion engine to function? a. Air, fuel, lubrication. b. Air, fuel, source of ignition. c. Fuel, ignition, lubrication. d. Fuel, compression, ignition. 2

2. Internal combustion engines are so named because: a. a spark is required to cause an explosion. b. burnt gases of the air-fuel mixture are expelled through the exhaust manifold. c. energy is derived from burning an air-fuel mixture in a confined combustion chamber. d. the piston traveling within the cylinder causes the air-fuel mixture to explode. 3

3. When the air-fuel mixture is ignited in the combustion chamber: a. pressure is exerted outward equally in all directions. b. pressure is exerted downward only. c. no pressure is exerted. d. pressure is exerted upwards only.

4. The bore of an engine is the: a. length of the stroke. b. taper of the cylinder bore. c. diameter of the cylinder bore. d. flange area of the intake manifold. 5

5. The measure of the amount of work an engine does is called: a. torque. b. horsepower. c. engine displacement. d. compression ratio. 6

6. Compression ratios of four-stroke cycle gasoline engines are: a. higher than diesel engines. b. lower than diesel engines. c. about the same as diesel engines. d. unrelated to engine power output. 7

b. correct ignition timing. c. higher compression ratio. 7. Generally, an increase in power and fuel economy is associated with: a. torque. b. correct ignition timing. c. higher compression ratio. d. removing air filters. 8

c. number of pistons required. 8. A basic difference between two-stroke and four-stroke cycle gasoline engines is the: a. type of fuel used. b. type of cooling used. c. number of pistons required. d. number of piston strokes required to complete a cycle. 9

a. the temperature to decrease. b. the pressure to decrease. 9. The compression of air in a modern four-stroke cycle diesel engine causes: a. the temperature to decrease. b. the pressure to decrease. c. air flow in the intake manifold. d. the air temperature in the cylinder to rise to approximately 1000° F (538° C). 10

10. The three basic methods of installing internal combustion engines to their drive systems are the: a. outboard drive system, the stern drive system, and the inboard drive system. b. stern drive system, the inboard/outboard drive system, and the outboard drive system. c. inboard drive system, the inboard/outboard drive system, and the jet drive system. d. outboard drive system, the jet drive system, and the inboard drive system. 11

11. The outboard drive system is unique because it: a. can use a larger propeller than the inboard drive system. b. is contained in one compact housing. c. can develop greater horsepower than the stern drive system. d. is the only drive system with a lower unit.

12. Inboard drive systems require: a. a separate propeller. b. a separate lower unit. c. a separate rudder. d. a separate power head. 13

13. The stern drive system is unique in that: a. it is always powered by 2-stroke cycle engines. b. it endows an inboard engine with the maneuverability of an outboard drive system. c. the engine is always mounted on the stern of the boat. d. the power transmitting shaft never pierces the hull of the boat. 14

14. Propeller size is determined by: a. diameter and engine rpm. b. diameter and pitch. c. number of blades and pitch. d. number of blades and diameter. 15

15. Increasing a propeller’s pitch will: a. increase the engine’s rpm. b. increase the boat’s maneuverability. c. decrease the engine’s rpm. d. decrease the boat’s maneuverability. 16

16. Replacing a propeller with a water jet enhances: a. shallow water operation. b. a boat’s steerage. c. a boat’s speed. d. thrust. 17

17. Four fundamental principles of troubleshooting marine engines are: a. check the easy, check the obvious, make all adjustments first, and keep a log. b. check the obvious, check the easy, check systematically, and make no erratic adjustments. c. make all necessary adjustments first, then check the easy, check systematically, and check the obvious. d. keep a log, check the easy, check the obvious, and check systematically. 18