Soldering does not produce the electric arc that welding does. Welders must cover all exposed skin with protective clothing and wear face shields with light filters for protection.
The vast majority of drill bits are made to cut while rotating in a clockwise direction (as viewed from above). These are known as right hand drill bits. (Notice that choices (B) and (C) are logically equivalent and therefore must be incorrect, as each question has only one correct answer.)
A motor oil with a “C” prefix for its quality rating would be suited for diesel engine use (i.e., a CD rating). Motor oil that had both an “S” and a “C” rating would be suited for either gasoline or diesel engine use. An example of this would be motor oil with a rating of SJ/CD.
Coil-on-plug ignition systems eliminate the need for spark plug wires because the ignition coil is mounted directly over the spark plugs. Secondary coil winding (A), spark plugs (C), and primary coil winding (D) are still necessary components in a coil-on-plug ignition system.
A double overhead cam arrangement puts two camshafts into each cylinder head, and makes it so one cam operates the exhaust valves in that head, and the other operates all the intake valves. Since the configuration of a V-8 engine has two heads, there would be a total of four camshafts.
This is a round rasp. Carpenters would use a round rasp for cleaning out holes in wood. Round rasps are useful for cleaning up holes, whereas a flat rasp would be used to smooth flat surfaces.
Using an oxyacetylene cutting torch involves the burning of oxygen and acetylene to produce a flame that is hot enough to melt steel.
All automotive electrical systems are designed to utilize direct current (DC). Some vehicles may use a negative ground as part of their electrical systems, but not all cars do, so (C) is incorrect.
As the lead-acid battery discharges, the sulphuric acid in the electrolyte is reduced to water. The lead plates then become lead sulphate. Charging the battery restores the chemical composition of the lead plates and the electrolyte.
The camshaft is responsible for the -opening and closing of the engine’s intake and exhaust valves. The camshaft turns at one-half the speed of the engine’s -crankshaft.
An outside micrometer is used to measure the outside dimensions of small things, such as cylinders, spheres, or relatively flat, thin objects.
The most common type of pliers is the combination slip-joint. These are adjustable at the joint of the two handles of the pliers. With two different positions to choose from, these pliers can grip objects in a wide range of sizes.
A coping saw is used to make fine, curving cuts. This saw uses a thin, flexible blade that is held tight on a wide frame.
The thermostat controls engine temperature by allowing coolant to flow into the radiator when the coolant temperature rises above a certain level.
Since the piston is moving downward and the intake valve is open, this image depicts the intake stroke, which is the first stroke in the four-stroke cycle.
A specific mixture of air and fuel plus an ignition source to get the whole thing going is required for combustion.
The firing order for four-cylinder engines is 1-3-4-2. Therefore, (A) is the answer.
It takes two full revolutions of the crankshaft to complete one cycle of events in a four-stroke cycle engine. This means that all of the cylinders in the engine must complete a power stroke in two revolutions of the crankshaft. So in one revolution, only three cylinders will fire. Thus, the correct answer is (B).
Claw hammers are a more specialized tool often preferred by carpenters. Their purpose is two-fold. The hammer head has two ends: One drives nails and the other removes them. This is the tool least likely to be found in a mechanic’s tool box.
Most solders are an alloy of lead and tin. The percentages of each metal in the solder will vary depending on the desired properties of the solder, i.e., melting point.
An automobile battery, or lead-acid battery, is made up of lead plates immersed in an electrolyte made up of sulphuric acid and water.
Moving the ignition switch to the “start” position sends an electrical current to the starter solenoid. This engages the starter drive gear onto the engine’s ring gear, which is located on the flywheel.
Sockets come in both 6- and 12-point designs. Six-point is a stronger design, and is usually the mechanic’s first choice in the smaller socket drive sizes. However, 12-point is definitely the most popular in large drive sizes.
The stoichiometric, or ideal, air-fuel ratio is 14.7:1. This means that 14.7 pounds of air is combined with 1 pound of fuel to create an ideal air-fuel mix.
It is the brake rotor attached to the wheel that rotates. Then the brake caliper clamps to slow the car wheels down. While a brake drum does rotate with the wheel, it is not a component of a disc brake system.