Engine Maintenance

1. Engine Maintenance Chapter 2 - Quiz

2. 1. The largest single component in an inboard engine is the: • a. intake manifold. • b. engine block. • c. exhaust manifold. • d. carburetor and flame arrestor. 2

3. 2. The principal purpose of the engine block is to: • a. enclose the cylinders. • b. support the carburetor. • c. hold the engine oil. • d. provide space for crankshaft timing.

4. 3. Steel or cast iron sleeves are used in aluminum engine blocks to: • a. support the crankshaft. • b. support the main bearings. • c. absorb high stress and wear. • d. absorb excess engine oil. 4

5. 4. Cylinder heads are: • a. removable and made of cast iron or aluminum. • b. removable and made of tough resilient material. • c. permanently machined with the engine block. • d. permanently machined with the crankshaft. 5

6. 5. The engine crankshaft: • a. is directly connected to the propeller. • b. is permanently attached to the valve train. • c. rotates around the flywheel. • d. rotates within journals and bearings. 6

7. 6. Piston rings: • a. are seldom used on four-stroke cycle engines. • b. are seldom used on two-stroke cycle engines. • c. prevent leakage from the combustion chamber. • d. are not used on diesel engines. 7

8. 7. The piston and crankshaft are connected together by the: • a. rocker arm. • b. camshaft. • c. connecting rod. • d. oil pump 8

9. 8. The purpose of the flywheel is to: • a. maintain momentum between power impulses. • b. maintain rotary motion of the pistons. • c. distribute power from the transmission. • d. distribute power from the valve train. 9

10. 9. The basic purpose of the camshaft is to: • a. oppose crankshaft vibration. • b. drive the alternator. • c. drive the water pump. • d. cause the valves to open and close. 10

11. 10. Marine engines used in inboard installations are usually of the “wet sump” design meaning the component closing the bottom of the crankcase is the: • a. water pump location. • b. alternator location. • c. oil pan that contains the lubricating oil reservoir. • d. reservoir where excess coolant is stored. 11

12. 11. Timing marks are sometimes found on the: • a. pistons. • b. crankshaft. • c. starter. • d. vibration damper. 12

13. 12. What is a proper precaution when fueling an inboard gasoline engine boat? • a. Open all hatches, ports, and doors. • b. Hold fuel nozzle a short distance from the filler opening. • c. Fill tank until fuel flows out of the vent pipe. • d. Close all windows, hatches, ports, and doors. 13

14. 13. Gasoline fumes (vapors) are: • a. the same weight as air. • b. heavier than air. • c. lighter than air. • d. odorless. 14

15. 14. The purpose of the carburetor is to: • a. control carbon in the engine. • b. provide the correct mixture of fuel and air to the cylinders. • c. time the engine. • d. pump fuel from the fuel tank. 15

16. 15. The primary difference between a carburetor system and a fuel injection system is the: • a. fuel injection system has a float chamber. • b. carburetor system uses a sensor to determine ambient air pressure. • c. carburetor system is electronically controlled. • d. fuel injector system meters fuel into the intake air system. 16

17. 16. Fuel filters are necessary to prevent: • a. vapor lock. • b. excessive fuel pressure. • c. foreign material from entering the carburetor or fuel injector. • d. gasoline fumes from entering the bilge. 17

18. 17. The two types of marine engine cooling systems are: • a. direct and open. • b. direct and restricted. • c. indirect and direct. • d. indirect and closed. 18

19. 18. In the indirect cooling system the coolant: • a. is circulated in a closed loop • b. is mixed with sea water to provide greater cooling properties • c. flows to the exhaust outlet pipe and is discharged overboard • d. is untreated and sometimes contains contamination 19

20. 19. In marine engine applications the three types of cooling system pumps are: • a. lift, centrifugal and gear. • b. centrifugal, gear and impeller. • c. gear, lift and impeller. • d. impeller, lift and centrifugal. 20

21. 20. The four primary functions of the lubricating systems are: • a. lubricating, sealing, pressurizing, and cooling. • b. lubricating, cleaning, pressurizing, and sealing. • c. sealing, cooling, pressurizing, and cleaning. • d. lubricating, sealing, cooling, and cleaning. 21

22. 21. The purpose of the oil filter is to: • a. remove paraffin from the oil. • b. remove foreign particles from the oil. • c. decrease the amount of water in the oil. • d. keep oil pressure from building. 22

23. 22. What is the primary source of energy commonly found in the ignition system of an inboard gasoline marine engine? • a. Self-generated. • b. Magneto. • c. Alkaline storage battery. • d. 12 volt storage battery. 23

24. 23. Battery voltage is not high enough to cause a spark discharge across the spark plug gap. What device is used to increase the voltage high enough to jump the gap? • a. Condenser. • b. Alternator. • c. Ignition coil. • d. Diodes. 24

25. 24. The most common method of recharging marine storage batteries is by means of: • a. a generator. • b. the ignition coil. • c. a voltmeter. • d. an alternator. 25

26. 25. Starter motors for marine engines: • a. should never be operated for more than 30 seconds at a time. • b. have no time restrictions. • c. are capable or delivering high energy over long periods of time. • d. are high voltage, low current motors. 26