Chapter 3

1. Chapter 3 Tools and Fasteners

2. Objectives (1 of 2) • List some of the common hand tools used in heavy-duty truck repair. • Describe how to use common pneumatic, electrical, and hydraulic power tools used in heavy-duty truck repair. • Identify the mechanical and electronic measuring tools used in the heavy-duty truck shop.

3. Objectives (2 of 2) • Describe the proper procedure for measuring with a micrometer. • Identify the types of manufacturer service literature used in truck repair facilities and describe the type of information each provides. • Explain the principles and precautions of working with various heavy-duty truck fasteners.

4. Hand Tools (1 of 2) • Hammer safety • Always wear eye protection when striking tempered tools and hardened metal surfaces. • Whenever possible, use soft-faced hammers when striking hardened surfaces. • Never strike one hammer against another. • Check the fit and condition of the handle.

5. Hand Tools (2 of 2) • Replace cracked or splintered handles and do not use the handle for prying or bumping. • Select the right size for the job. • Grip the handle close to the end. • Prevent injuries to others. • Swing in a direction that will not let your hammer strike someone if it slips from your hand. • Keep the handle dry and free of grease and oil. • Keep the hammer face parallel with your work.

6. Saw and Knife Safety (1 of 2) • Keep knife blades sharp. • Cut away from the body. • Never pry with a knife or saw blade. • Store knives safely.

7. Saw and Knife Safety (2 of 2) • Before completing a saw cut, slow down to avoid injury as the saw finishes the cut. • Never use a damaged blade. • Always wear safety glasses when using a hacksaw. • Do not use the thumb as a guide in starting a hacksaw. • Use full travel, even strokes to maximize the life of the blade.

8. Chisel and Punch Safety • Wear eye protection when cutting with a chisel or using a punch. • Avoid using a punch or chisel on hardened metal. • Grind off mushroom heads before using a chisel or punch. • Do not drive a punch too deep into a bore or it may become wedged due to its taper.

9. Screwdrivers • Standard tip screwdrivers • Phillips screwdrivers • Specialty screwdrivers • Safety • Use screwdrivers only for turning screws. • A slotted screwdriver tip can easily be dressed to its original shape. • If the screwdriver blade fits the screw slot properly, you will produce maximum torque with minimum effort.

10. Screwdriver Safety • It is a good rule to keep your other hand clear when applying force to any type of screwdriver. • Always have the screwdriver and the screw correctly lined up. • Screwdrivers designed for use with wrenches have either a square shank or a hex bolster at the handle. • Do not hold components in your hand while turning fasteners with a screwdriver. • When working around anything electrical, use a screwdriver with an insulated handle and shank to avoid shock and short circuits.

11. Wrenches • Open-end wrenches • Box-end wrenches • Combination wrenches • Adjustable wrenches • Allen wrenches • Socket wrenches

12. Wrench Safety (1 of 2) • Use wrenches that fit. • Wrenches that slip damage bolt heads and nuts, skin knuckles, and cause the user to fall. • Use the proper wrench to get the job done—the one that gives you the surest grip and a straight clean pull. • Do not extend the length of a wrench. • Do not use a hammer on wrenches unless they are designed for that type of use.

13. Wrench Safety (2 of 2) • Pull on the wrench. • Use an open palm to push on a wrench when you cannot pull it toward you. • Replace damaged wrenches. • The adjustable wrench is a multi-purpose tool, but it should never be used if a properly fitting combination wrench is at hand.

14. Pliers • Combination pliers • Adjustable pliers • Adjustable pliers • Locking pliers • Diagonal cutting pliers

15. Plier and Cutter Safety • Do not use pliers as a wrench. • Guard against eye injuries when cutting with pliers or cutters. • Observe the following side-cutter precautions: • Select a cutter big enough for the job. • Keep the blades at right angles to the stock. • Do not rock the cutter to get a faster cut. • Adjust the cutters to maintain a small clearance between the blades. • Pliers are made for holding, pinching, squeezing, and cutting—not usually for turning.

16. File Safety • Wear eye protection when filing. • Never strike a file with a hammer. • Always cut away from the body. • Never use a file without a securely attached handle. • Do not use worn (dull) files; replace them.

17. Special Tools • Taps and dies • Gear and bearing pullers

18. Power Tools Safety (1 of 7) • Return all equipment to its proper place when finished. • Wear eye protection. • Noise may be a hazard with some portable power tools, especially pneumatic tools. • Wear hearing protection whenever noise is excessive. • Wear gloves when operating air chisels or air hammers. • All electrical equipment should be grounded, unless it is the double insulated type.

19. Power Tools Safety (2 of 7) • Never make adjustments, lubricate, or clean a machine while it is running. • Do not clean yourself or anyone else with compressed air. • Report any suspect or malfunctioning machinery to the instructor or service manager. • Know your power tool.

20. Power Tools Safety (3 of 7) • Do not abuse the electric power cord. • Never yank it to disconnect it from a receptacle. • No machine should be started unless guards are in place and in good condition. • Check and make all adjustments before applying power. • Give the machine your undivided attention while you are using it.

21. Power Tools Safety (4 of 7) • Inspect all equipment for safety and for apparent defects before using. • Whenever safeguards or devices are removed to make repairs or adjustments, equipment should be turned off and the main switch locked and tagged. • Start and stop your own machine and remain with it until it has come to a complete stop. • Always allow any machine to reach operating speed before loading it. • No attempt should be made to retard rotation of the tool or work.

22. Power Tools Safety (5 of 7) • Do not try to strip broken belts or other debris from a pulley in motion or reach between belts and pulleys. • Do not use loose rags around operating machinery. • Use the right tool. • Maintain tools with care.

23. Power Tools Safety (6 of 7) • Remove adjusting keys and wrenches. • Do not overreach. • Maintain a balanced stance to avoid slipping. • Disconnect tools when not in use, before servicing, or when changing attachments, blades, bits, cutters, and so on. • Before plugging in any electric tool or machine, make sure the switch is off. • Remove all sharp edges and burrs before completing any job.

24. Power Tools Safety (7 of 7) • Impact wrenches • Air ratchet wrenches • Air drills • Air chisels and hammers • Blowgun

25. Other Power Tools • Bench grinders • Lifts and hoists • Presses

26. Lift and Hoist Safety (1 of 2) • Do not let anyone remain in a vehicle when it is being raised. • Make certain you know how to operate the equipment and know its limitations. • Never overload a lift, hoist, or jack. • Chain hoists and cranes must be properly attached to the parts being lifted. • Always use bolts and shackles of sufficient strength rating to attach the hoist to the object being lifted.

27. Lift and Hoist Safety (2 of 2) • Mechanical locks or stands must be engaged after lifting a truck on any kind of hoist. • Do not use any lift, hoist, or jack that you believe to be defective or not operating properly. • Make sure all persons and obstructions are clear before raising or lowering an engine or vehicle. • Avoid working, walking, or standing under suspended objects that are not mechanically supported.

28. Measuring Tools • Machinist’s rule • Dial calipers • Micrometers • Inside micrometer • Outside micrometer • Depth micrometer

29. Reading an Inch-Graduated Outside Micrometer • To read a micrometer, first read the last whole sleeve number visible on the sleeve index line. • Next, count the number of full sleeve graduations past the number. • Finally, count the number of thimble graduations past the sleeve graduations. • Add these together for the measurement. • These three readings indicate tenths, hundredths, and thousandths of an inch, respectively.

34. Using an Outside Micrometer

35. Reading an Inside Micrometer

36. Other Measuring Gauges • Thickness gauges • Screw pitch gauges • Torque-indicating wrenches

37. Manufacturers’ Service Publications • Service manuals • Parts books • Service bulletins • Recall bulletins • Field service modifications • Time guides • Driver’s manuals

38. Other Service Publications • Supplier manufacturers’ guides and catalogs • General repair literature

39. Fasteners • Fastener grades and classes • Frame fasteners • Tightening fasteners • Fastener replacement • Thread repair • Screw/stud removers and extractors • Thread locking compound application

40. Fastener Tightening (1 of 3) • Clean all fasteners, threads, and all surfaces before installing them. • Ensure they are torqued accurately. • When locking compound or anti-seize compound is recommended for a fastener, the compound acts as a lubricant, and oil is not needed. • Hand turn fasteners so they contact before using a torque wrench to tighten them to their final torque values. • Tighten the nut, not the bolt head, when possible. • This gives a truer torque reading by eliminating bolt body friction.

41. Fastener Tightening (2 of 3) • Always use a torque wrench to tighten fasteners, and use a slow, smooth, even pull on the wrench. • When reading a bar type torque wrench, look straight down at the scale. • Viewing from an angle can give a false reading. • Only pull on the handle of the torque wrench. • Do not allow the beam of the wrench to touch anything. • Tighten bolts and nuts incrementally. • Typically, this should be to one-half specified torque, to three-fourth torque, to full torque, and then to full torque a second time.

42. Fastener Tightening (3 of 3) • Do not over-torque fasteners. • Overtightening causes permanent stretching of fasteners, which can result in breakage of parts or fasteners. • If specific torque values are not given for countersunk bolts, use the torque value for the corresponding size and grade of regular bolt. • Follow the torque sequence when provided to ensure that clamping forces are even and mating parts and fasteners are not distorted.

43. Shop Talk • If a torque-to-yield bolt is replaced with a new bolt of identical grade but torqued to a value found in a standard torque chart, the clamping force produced will be at least 25 percent less.

44. Adhesives and Chemical Sealing Materials • Chemical adhesives and sealants may provide added holding force and sealing ability when two components are joined. • Sealants are applied to threads where fluid contact is frequent. • Chemical thread retainers are either: • Aerobic (cures in the presence of air) • Anaerobic (cures in the absence of air) • When using a chemical adhesive or sealant, follow the manufacturer’s instructions. • Note that some adhesives molecularly bond to the surface of metals, destroying the material on removal.

45. Shop Talk • To disassemble fasteners that have been held together with a thread locking compound, it may be necessary to heat the bond line to 400°F before removing the nut. • Every time the fasteners are disassembled, replace them. • If mating components are damaged by overheating, replace them.

46. Summary (1 of 4) • Hand tools are used in many repair tasks. • Proper selection and use of hand tools by the technician are important requirements for performing quality heavy-duty truck service. • Power tools make a technician’s job easier. • Pneumatic (air) tools have four advantages over electrically powered equipment: flexibility, light weight, safety, and low cost operation and maintenance. • The disadvantage is the noise produced. • Power tool safety rules must be followed and that includes wearing hearing protection.

47. Summary (2 of 4) • The power tools used in heavy-duty truck repair include impact wrenches, air ratchet wrenches, air drills, air chisels and hammers, blowguns, bench grinders, grinding wheels, wire wheel brushes, buffing wheels, presses, and lifts and hoists. • Using jacks, lifts, frame machines, and hoists to raise trucks, trailers, or heavy parts on a truck chassis requires careful adherence to safety rules. • The machinist’s rule looks like an ordinary ruler, but it is precisely divided into small increments, either in metric or decimal graduations.

48. Summary (3 of 4) • Dial or digital calipers are used for taking inside, outside, depth, and step measurements, and are calibrated to read in either metric or standard scales. • A micrometer is used for measuring the inside or outside diameter of a shaft or the bore of a hole, either in metric or standard units. • Gauges are used to measure thickness and screw pitch. • A torque wrench is used to measure the amount of twisting force applied in tightening a fastener. • The main source of repair and specification information for heavy-duty trucks is the OEM service literature available in manuals, on CDs, or on-line from manufacturer data hubs.

49. Summary (4 of 4) • Troubleshooting charts are provided in manuals or on-line to provide a way to systematically track problem sources and identify the repair required. • Fasteners used on heavy-duty trucks come in a range of grades and classes. • Proper use of torque wrenches is necessary when installing threaded fasteners. • The correct fastener is important. In some cases, threads must be repaired with thread inserts or by thread chasing. • Rivets are used to fasten overlapping skin panels on a truck cab and some trailer skins. • A rivet gun and bucking bar are used to drive and buck rivets.