Auto Chapter 6 sections 1,2, and 6
Chassis Dynamometers
A chassis dynamometer is a device that allows a vehicle to be run at road speed while safely contained within a shop bay. Chassis dynamometers are very useful for tuning engines, testing vehicle performance, and determining output in torque and horsepower. They are also used with sensors and test instruments to create simulated load conditions and diagnose any faults while in the shop. Chassis dynamometers are usually bolted down to the floor or built into the floor and have rollers that the wheels sit on. The vehicle is chained down so it cannot move forward or backward when the accelerator is pressed down. The chassis dynamometer has a control unit that displays the controls for the dynamometer and selected engine parameters such as engine revolutions per minute (rpm), drive wheel torque, and power.
CLEANING TOOLS AND EQUIPMENT
Clean tools and equipment work more safely and efficiently. At the end of each working day, clean the tools and equipment you used and check them for any damage. If you note any damage, tag the tool as faulty and organize a repair or replacement. Electrical current can travel over oily or greasy surfaces. Be sure to keep electrical power tools clean. All shop equipment should have a maintenance schedule. Always complete the tasks described on the schedule at the required time. This will help to keep the equipment in safe working order. Store commonly used tools in an easy-to-reach location. If a tool or piece of equipment is too difficult to return, then it will likely be left on a workbench or on the floor where it will become a safety hazard. Keep your work area tidy. This will help you work more efficiently and safely. Keep a trash can close to your work area and place any waste in it as soon as possible. Dispose of liquid and solid waste, such as oils, coolant, and worn components, in the correct manner. Local authorities provide guidelines for waste disposal with fines for noncompliance. When cleaning products lose their effectiveness, they will need to be replaced. Refer to the supplier's recommendations for collection or disposal. Do not pour solvents or other chemicals into the sewage system. This is both environmentally damaging and illegal. Always use chemical gloves when using any cleaning material because excessive exposure to cleaning materials can damage skin. Also, absorbing some chemicals through the skin over time can cause permanent harm to your body. Some solvents are flammable; never use cleaning materials near an open flame or cigarette. The fumes from cleaning chemicals can be toxic, so wear appropriate respirator and eye protection wherever you are using these products. To keep work areas and equipment clean and operational, follow the steps in SKILL DRILL 6-35: 1 Clean hand tools. Keep your hand tools in good, clean condition with two types of rags. One rag should be lint-free to clean or handle precision instruments or components. The other should be oily to prevent rust and corrosion. (Photo 1) 2 Clean floor jacks. Wipe off any oil or grease on the floor jack and check for fluid leaks. If you find any, remove the jack from use and have it repaired or replaced. Occasionally, apply a few drops of lubricating oil to the wheels and a few drops to the posts of threaded jack stands. (Photo 2) 3 Clean electrical power tools. Keep power tools clean by brushing off any dust and wiping off excess oil or grease with a clean rag. Inspect any electrical cables for dirt, oil, or grease, and for any chafing or exposed wires. With drills, inspect the chuck and lubricate it occasionally with machine oil. (Photo 3) 4 Clean air-powered tools. Apply a few drops of oil into the inlet of your air tools every day. Although these tools have no electrical motor, they do need regular lubrication of the internal parts to prevent wear. (Photo 4) 5 Clean hoists and heavy machinery. Locate the checklist or maintenance record for each hoist or other major piece of equipment before carrying out cleaning activities. 6 You should clean equipment operating mechanisms and attachments of excess oil or grease. (Photo 5)
Standard and Metric Designations
Many tools, measuring instruments, and fasteners come in United States customary system (USCS) sizes, more commonly referred to as "standard," or in metric sizes. Tools and measuring instruments can be identified as standard or metric by markings identifying their size on tools or the increments on a measuring tool. Fasteners bought new will have their designation identified on the packaging. Other fasteners may have to be measured by a ruler or vernier caliper to identify their designation. Manufacturer's charts showing thread and fastener sizing will assist in identifying standard or metric sizing. To identify standard and metric designation, follow these steps: 1. Examine the component, tool, or fastener to see if any marking identifies it as standard or metric. Manufacturer specifications and shop manuals can be referred to and may identify components as standard or metric. 2. If no markings are available, use measuring devices to gauge the size of the item and compare thread and fastener charts to identify the sizing. Inch-to-metric conversion charts will assist in identifying component designation.
Tool Location
The shop will usually have a selection of tools available for use, and these tools will be located in a number of areas. They include specialized manufacturer tools, high-cost tools, and tools that are not portable, such as hoists and compressors. Technicians will have a selection of their own tools, which will include various hand tools and electrical meters. Often they will add to their toolbox over time. To identify tools and their usage in automotive application, follow these steps: 1. Create a list of tools in your tool chest and identify their application for automotive repair and service. 2. Look through the shop's tool storage areas and create a list of the tools found in each storage area; identify their application for automotive repair and service.
Compressed Air Equipment
The term compressed air equipment covers a wide range of tools and equipment required in a compressed air system. Tools that use compressed air include drills, grinders, pumps, grease guns, jacks, and impact wrenches FIGURE 6-2. The compressed air system is made up of a compressor, a pressure regulator, air hose or fixed piping, and the actual tool or item that is powered by the compressed air. The air compressor has a storage tank and is driven by an electric motor or, for more portability, a gasoline engine. In many shops, the air compressor is housed in a separate room to help isolate the noise. Standard compressors have been, and still are, based on piston-type compressors, which operate similar to a piston engine where each piston compresses the air on the compression stroke. But in the case of a compressor, the piston forces the air out of the cylinder and into a storage tank under pressure. Many newer air compressors are of the scroll compressor type, which uses a pair of rotating scrolls to compress the air and is much quieter and more efficient. With either type of compressor, a pressure regulator controls the air pressure being supplied to the distribution system while the air hose or lines transport the compressed air from the compressor to the tool. Compressed Air Safety Serious, sometimes fatal, injuries can be caused by compressed air being injected into the body through the skin or into a body opening, such as your mouth or ear. Do not play with air equipment, such as blowing air at another person or yourself. Internal human blood vessels and organs will rupture at much lower pressures than those found in compressed air lines. So always handle air equipment carefully and with respect. Be extra careful when working with air equipment in a confined or awkward space, such as under a vehicle, and when clearing or cleaning the equipment.
Tool Usage
Tools extend our abilities to perform many tasks; for example, jacks, stands, and hoists extend our ability to lift and hold heavy objects. Hand tools extend our ability to perform fundamental tasks like gripping, turning, tightening, measuring, and cutting. Electrical meters enable us to measure things we cannot see, feel, or hear, while power and air tools multiply our strength by performing tasks quickly and efficiently. As you are working, always think about what tool can make the job easier, safer, or more efficient. As you become familiar with more tools, your productivity, quality, and effectiveness will improve. Every tool is designed to be used in a certain way to do the job safely. It is critical to use a tool in the way it is designed to be used and to do so safely. For example, a screwdriver is designed to tighten and loosen screws, not to be used as a chisel. Ratchets are designed to turn sockets, not to be used as a hammer. Think about the task you are undertaking, select the correct tools for the task, and use each tool as it was designed.
Work Safe and Stay Safe
Whenever using tools, always think safety first. There is nothing more important than your personal safety. If tools (both hand and power) are used incorrectly, you can potentially injure yourself and others. Always follow equipment and shop instructions, including the use of recommended personal protective equipment (PPE). Accidents only take a moment to occur but can take a lifetime to recover from. You are ultimately responsible for your safety, so remember to work safe and stay safe. Safe Handling and Use of Tools Tools must be safely handled and used to prevent injury and damage. Always inspect tools prior to use and never use damaged tools. Check the manufacturer and the shop procedures or ask your supervisor if you are uncertain about how to use tools. Inspect and clean tools when you are finished using them. Always return tools to their correct storage location. To safely handle and use appropriate tools, follow the steps in SKILL DRILL 6-1: 1 Select the correct tool(s) to undertake tasks. 2 Inspect tools prior to use to ensure they are in good working order. If tools are faulty, remove them from service according to shop procedures. (Photo 1) 3 Clean tools prior to use if necessary. (Photo 2) 4 Use tools to complete the task while ensuring manufacturer and shop procedures are followed. Always use tools safely to prevent injury and damage. 5 Ensure tools are clean and in good working order afteruse. Report and tag damaged tools, and remove them from service following shop procedures. (Photo 3) 6 Return tools to correct storage locations. (Photo 4)Some tools are heavy or awkward to use, so seek assistance if required and use correct manual handling techniques when using tools. To utilize safe procedures for handling tools and equipment, follow the steps in SKILL DRILL 6-2: 1 Seek assistance if tools and equipment are too heavy or too awkward to be managed by a single person. 2 Inspect tools and equipment for possible defects before starting work. 3 Report and/or tag faulty tools and equipment according to shop procedures. (Photo 1) 4 Select and wear appropriate PPE for the tools and equipment being used. (Photo 2) 5 Use tools and equipment safely. 6 Check tools for faults after using them and report and/or tag faulty tools and equipment according to shop procedures. 7 Clean and return tools and equipment to correct storage locations when tasks are completed. (Photo 3) SKILL DRILL6-2
GENERAL GUIDELINES
While it is important to be trained on the safe use of tools and equipment, it is even more critical to have a safe attitude. A safe attitude will help you avoid being involved in an accident. Students who think they will never be involved in an accident will not be as aware of unsafe situations as they should be. And that can lead to accidents. So while we are covering the various tools and equipment you will encounter in the shop, pay close attention to the safety and operation procedures. Tools are a technician's best friend, but if used improperly, they can injure or kill.
Air Driers and Automatic Oilers
are fitted to compressed air systems to remove the moisture or water from the compressed air that is condensed as a result of compressing air from the atmosphere, which contains water in the form of humidity. If water gets into the air lines, it may damage air tools. Air driers can be a stand-alone device fitted to the compressed air system or incorporated into a filter/regulator system. The combination filter/regulator system removes water from the air, filters any debris that may come from the compressor tank, and regulates the line pressure from the tank.
Lockout/Tagout
is an umbrella term that describes a set of safety practices and procedures that are intended to reduce the risk of technicians inadvertently using tools, equipment, or materials that have been determined to be unsafe or potentially unsafe or that are in the process of being serviced. An example of lockout would be physically securing a broken, unsafe, or out-of-service tool so that it cannot be used by a technician. In many cases, the item is also tagged out so it is not inadvertently placed back into service or operated. An example of tagout would be affixing a clear and unavoidable label to a piece of equipment that describes the fault found, the name of the person who found the fault, the date that the fault was found, and that warns not to use the equipment