Question

use the first half of chapter 15 (pg. 142 - 145) to help you answer the questions. 1. what part of the engine holds the pistons? 2. what part of the engine contains the valves? 3. what part starts combustion in a gasoline engine? a. the heat from compression b. the intake valves c. the spark plug d. the glow plug 4. technician a states that the intake and exhaust valves are closed during the compression stroke. technician b states the intake and exhaust valves are closed during the power stroke. who is correct? a. technician a b. technician b c. both technicians. d. neither technician. 5. how many times will the crankshaft rotate to complete all four strokes of the four - stroke cycle? a. 1 b. 2 c. 4 d. 6 6. how many cylinder heads are found on an inline 4 - cylinder engine? a. 1 b. 2 c. 6 d. 4 7. how many cylinder heads are found on a v6 engine? a. 1 b. 2 c. 6 d. 4 8. coolant flow through the radiator is controlled by the a. size of the passages in the block b. thermostat c. cooling fan(s) d. water pump 9. the four strokes of a 4 stroke engine cycle in order are _, _, _, and _. 10. during the intake stroke the crankshaft rotates ___ degrees.

Explanation:

1. The cylinder block holds the pistons. It provides a housing for the pistons to move up and down within the engine.
2. The cylinder head contains the valves. It sits on top of the cylinder block and houses the intake and exhaust valves.
3. In a gasoline engine, the spark plug starts combustion. It ignites the air - fuel mixture in the combustion chamber.
4. Both technicians are correct. During the compression stroke, the intake and exhaust valves are closed to compress the air - fuel mixture, and during the power stroke, they are also closed to allow the combustion gases to push the piston down.
5. The crankshaft rotates 2 times to complete all four strokes of the four - stroke cycle. Each full rotation of the crankshaft corresponds to two strokes in a four - stroke engine.
6. An inline 4 - cylinder engine has 1 cylinder head. All the cylinders share a single cylinder head.
7. A V6 engine typically has 2 cylinder heads, one for each bank of cylinders.
8. Coolant flow through the radiator is controlled by the thermostat. It regulates the temperature of the coolant by opening and closing to allow or restrict coolant flow to the radiator.
9. The four strokes of a 4 - stroke engine cycle in order are intake, compression, power, and exhaust.
10. During the intake stroke, the crankshaft rotates 180 degrees.

Answer:

1. Cylinder block
2. Cylinder head
3. c. The spark plug
4. c. Both technicians
5. b. 2
6. a. 1
7. b. 2
8. b. Thermostat
9. Intake, compression, power, exhaust
10. 180