GoodheartWillcox Co Inc 9 Topics q Fasteners q

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© Goodheart-Willcox Co. , Inc.

© Goodheart-Willcox Co. , Inc.

(9 Topics) q Fasteners q Washers q Machine screws q Sheet metal screws q

(9 Topics) q Fasteners q Washers q Machine screws q Sheet metal screws q Nonthreaded fasteners © Goodheart-Willcox Co. , Inc.

q Torquing bolts and nuts q Thread repairs q Removing damaged fasteners q Gaskets

q Torquing bolts and nuts q Thread repairs q Removing damaged fasteners q Gaskets and seals © Goodheart-Willcox Co. , Inc.

q Devices that hold the parts of a car together q Thousands of fasteners

q Devices that hold the parts of a car together q Thousands of fasteners are used in vehicles © Goodheart-Willcox Co. , Inc.

Automotive Fasteners © Goodheart-Willcox Co. , Inc.

Automotive Fasteners © Goodheart-Willcox Co. , Inc.

Bolts and Nuts q Bolt m metal rod with external threads on one end

Bolts and Nuts q Bolt m metal rod with external threads on one end a head on the other m when a bolt is threaded into a part other than a nut, it can also be called a cap screw q Nut m has internal threads and a six-sided outer shape © Goodheart-Willcox Co. , Inc.

Bolts and Nuts When a nut is screwed onto a bolt, a powerful clamping

Bolts and Nuts When a nut is screwed onto a bolt, a powerful clamping force is produced © Goodheart-Willcox Co. , Inc.

Bolt Dimensions © Goodheart-Willcox Co. , Inc.

Bolt Dimensions © Goodheart-Willcox Co. , Inc.

Bolt Dimensions © Goodheart-Willcox Co. , Inc.

Bolt Dimensions © Goodheart-Willcox Co. , Inc.

Thread Types q There are three basic types of threads used on fasteners: q

Thread Types q There are three basic types of threads used on fasteners: q Coarse threads m UNC-Unified National Coarse q Fine threads m UNF-Unified National Fine q Metric threads m SI © Goodheart-Willcox Co. , Inc.

Thread Direction q Bolts and nuts come in right- and lefthand threads q Right-hand

Thread Direction q Bolts and nuts come in right- and lefthand threads q Right-hand threads m fastener must be turned clockwise to tighten q Left-hand threads m fastener must be turned counterclockwise to tighten m letter L may be stamped on fastener © Goodheart-Willcox Co. , Inc.

Bolt Grade q Also called tensile strength q Refers to the amount of pull

Bolt Grade q Also called tensile strength q Refers to the amount of pull a fastener can withstand before breaking q Bolt head markings specify the tensile strength of the bolt q U. S. customary bolts are marked with lines q Metric bolts are marked with numbers © Goodheart-Willcox Co. , Inc.

Bolt Designation Number Gives information about the bolt © Goodheart-Willcox Co. , Inc.

Bolt Designation Number Gives information about the bolt © Goodheart-Willcox Co. , Inc.

Bolt Designation Number Used when purchasing new bolts © Goodheart-Willcox Co. , Inc.

Bolt Designation Number Used when purchasing new bolts © Goodheart-Willcox Co. , Inc.

Bolt Designation Number © Goodheart-Willcox Co. , Inc.

Bolt Designation Number © Goodheart-Willcox Co. , Inc.

Nut Types Common types of nuts used in vehicles © Goodheart-Willcox Co. , Inc.

Nut Types Common types of nuts used in vehicles © Goodheart-Willcox Co. , Inc.

Castle Nut and Cotter Pin Cotter pin keeps the nut from turning and possibly

Castle Nut and Cotter Pin Cotter pin keeps the nut from turning and possibly coming off © Goodheart-Willcox Co. , Inc.

q Used under bolt heads and nuts q Two basic types of washers used:

q Used under bolt heads and nuts q Two basic types of washers used: m flat washers m lock washers © Goodheart-Willcox Co. , Inc.

Washer Types q Flat washer m increases the clamping surface under the fastener m

Washer Types q Flat washer m increases the clamping surface under the fastener m prevents the bolt or nut from digging into the part q Lock washer m prevents the bolt or nut from becoming loose under stress and vibration © Goodheart-Willcox Co. , Inc.

Washer Types q Lock tabs or lock plates m perform the functions of both

Washer Types q Lock tabs or lock plates m perform the functions of both flat washers and lock washers m increase clamping surface area and secure the fastener © Goodheart-Willcox Co. , Inc.

Washer Types A. Plain flat washer C. Toothed lock washer © Goodheart-Willcox Co. ,

Washer Types A. Plain flat washer C. Toothed lock washer © Goodheart-Willcox Co. , Inc. B. Split lock washer D. Lock plate

q Similar to bolts, but they normally have screw-type heads q Threaded along their

q Similar to bolts, but they normally have screw-type heads q Threaded along their full length q Used to secure parts when clamping loads are light q Available in various head shapes © Goodheart-Willcox Co. , Inc.

q Also called tapping screws q Commonly used on plastic and sheet metal parts

q Also called tapping screws q Commonly used on plastic and sheet metal parts such as body trim, dashboard panels, and grills q Use tapering threads that are widely spaced © Goodheart-Willcox Co. , Inc.

Sheet Metal Screws Basic types of tapping screws © Goodheart-Willcox Co. , Inc.

Sheet Metal Screws Basic types of tapping screws © Goodheart-Willcox Co. , Inc.

Numerous types of nonthreaded fasteners, such as snap rings, clips, and adhesives, are used

Numerous types of nonthreaded fasteners, such as snap rings, clips, and adhesives, are used in the assembly of a vehicle © Goodheart-Willcox Co. , Inc.

Snap Ring q Fits into a groove in a part and commonly holds shafts,

Snap Ring q Fits into a groove in a part and commonly holds shafts, bearings, gears, pins, and other similar components in place q Snap ring pliers are needed to remove and install a snap ring mspecial jaws grasp the snap ring © Goodheart-Willcox Co. , Inc.

Snap Ring Types © Goodheart-Willcox Co. , Inc.

Snap Ring Types © Goodheart-Willcox Co. , Inc.

Keys and Set Screws q Key m fits into a keyseat (slot) cut into

Keys and Set Screws q Key m fits into a keyseat (slot) cut into a shaft and a keyway cut into the mating part q Set screw m normally used to lock a part onto a shaft m not as strong as a key © Goodheart-Willcox Co. , Inc.

Keys and Set Screws A. Key B. Set screw © Goodheart-Willcox Co. , Inc.

Keys and Set Screws A. Key B. Set screw © Goodheart-Willcox Co. , Inc.

Splines q Series of slots cut into a shaft and a mating part q

Splines q Series of slots cut into a shaft and a mating part q Allow the gear or collar to slide on the shaft but still not rotate q Used in manual transmissions, clutches, and drive shaft yokes © Goodheart-Willcox Co. , Inc.

Splines © Goodheart-Willcox Co. , Inc.

Splines © Goodheart-Willcox Co. , Inc.

Adhesives q Special glues widely used in vehicles q Used to hold body moldings,

Adhesives q Special glues widely used in vehicles q Used to hold body moldings, rubber weather stripping, and body emblems q Some stay soft and pliable while others dry hard q Some take hours to dry while others dry in seconds q Observe all directions and safety precautions when using adhesives © Goodheart-Willcox Co. , Inc.

It is very important that bolts and nuts are tightened properly–this is called torquing

It is very important that bolts and nuts are tightened properly–this is called torquing © Goodheart-Willcox Co. , Inc.

Torque Specifications q Tightening values given by the auto manufacturer q Normally given for

Torque Specifications q Tightening values given by the auto manufacturer q Normally given for all precision assemblies, such as engines, transmissions, and differentials q Factory specifications should be used m general bolt torque chart may be used if factory specs are not available © Goodheart-Willcox Co. , Inc.

Bolt Torque Chart © Goodheart-Willcox Co. , Inc.

Bolt Torque Chart © Goodheart-Willcox Co. , Inc.

Torque-to-yield q Requires a specific bolt torque, followed by turning the bolt a specific

Torque-to-yield q Requires a specific bolt torque, followed by turning the bolt a specific number of degrees q Procedure stretches the bolt to its correct yield point, preloading the fastener q New bolts may be required each time © Goodheart-Willcox Co. , Inc.

Torque Stretch q Determined by measuring bolt length change while torquing the bolt m

Torque Stretch q Determined by measuring bolt length change while torquing the bolt m when building a racing engine, you can “mike” connecting rod bolts to measure the length before and after tightening q Too much stretch indicates bolt weakness q Not enough stretch may indicate thread problems affecting torque © Goodheart-Willcox Co. , Inc.

Bolt Tightening Sequence q Used to make sure that parts are fastened evenly q

Bolt Tightening Sequence q Used to make sure that parts are fastened evenly q Creates an even, gradual clamping force along the entire mating surface of the parts q Crisscross pattern is often recommended © Goodheart-Willcox Co. , Inc.

Bolt Tightening Sequence Service manual pattern for a cylinder head © Goodheart-Willcox Co. ,

Bolt Tightening Sequence Service manual pattern for a cylinder head © Goodheart-Willcox Co. , Inc.

Bolt Tightening Sequence Service manual pattern for wheel lug nuts © Goodheart-Willcox Co. ,

Bolt Tightening Sequence Service manual pattern for wheel lug nuts © Goodheart-Willcox Co. , Inc.

Torque Wrench Rules q Keep a steady pull on the wrench q Clean fastener

Torque Wrench Rules q Keep a steady pull on the wrench q Clean fastener threads q Avoid using swivel joints q When reading a torque wrench, look straight down at the scale q Use manufacturer’s specifications when available © Goodheart-Willcox Co. , Inc.

Torque Wrench Rules q When manufacturer’s specs are not available, use general specs in

Torque Wrench Rules q When manufacturer’s specs are not available, use general specs in a crisscross pattern q To avoid a false reading, pull only on the handle q Tighten bolts and nuts in four steps q Retorque when required m some assemblies must be retightened after operation and heating © Goodheart-Willcox Co. , Inc.

Threaded holes in parts can become damaged, requiring repairs. A technician must be capable

Threaded holes in parts can become damaged, requiring repairs. A technician must be capable of repairing damaged threads quickly and properly © Goodheart-Willcox Co. , Inc.

Minor Thread Repairs Minor damage can be repaired with a thread chaser or thread

Minor Thread Repairs Minor damage can be repaired with a thread chaser or thread file © Goodheart-Willcox Co. , Inc.

Major Thread Repairs q Badly smashed or stripped threads may be repaired with either

Major Thread Repairs q Badly smashed or stripped threads may be repaired with either a tap or die q Tap m threaded tool for cutting internal threads in holes q Die m cuts external threads on metal rods, bolts, shafts, and pins © Goodheart-Willcox Co. , Inc.

Tap and Die © Goodheart-Willcox Co. , Inc.

Tap and Die © Goodheart-Willcox Co. , Inc.

Using a Tap and Die q Hold the handle squarely with the work q

Using a Tap and Die q Hold the handle squarely with the work q Back the handle off to clean metal out of the threads q Use a taper tap to start the threads q Use a plug tap and a bottoming tap to cut the threads to the bottom of a blind hole © Goodheart-Willcox Co. , Inc.

Tap and Die Rules q Never force a tap handle or the tool may

Tap and Die Rules q Never force a tap handle or the tool may break q Keep the tap and die well oiled to ease cutting q Use coarse threads when threading or tapping into soft metal, like aluminum m coarse threads will hold better than fine threads © Goodheart-Willcox Co. , Inc.

Tapping Oversize q When threads cannot be restored, the hole can be drilled and

Tapping Oversize q When threads cannot be restored, the hole can be drilled and tapped oversize q Use a “drill and tap size chart” to choose a drill bit and tap q Drill the hole one size larger than the original hole q Cut new threads in the drilled hole q Use a larger bolt in the threaded hole © Goodheart-Willcox Co. , Inc.

Thread Repair Insert q Used when the use of an oversize hole and fastener

Thread Repair Insert q Used when the use of an oversize hole and fastener is not acceptable q Takes place of damaged internal threads q Allows the use of the original-size bolt © Goodheart-Willcox Co. , Inc.

Using an Insert A. Drill the hole oversize B. Tap the hole oversize C.

Using an Insert A. Drill the hole oversize B. Tap the hole oversize C. Mount the insert on a mandrel D. Thread the insert into the hole © Goodheart-Willcox Co. , Inc.

Using an Insert allows the use of the original-size bolt © Goodheart-Willcox Co. ,

Using an Insert allows the use of the original-size bolt © Goodheart-Willcox Co. , Inc.

Using an Insert Damaged threads before a repair © Goodheart-Willcox Co. , Inc. Installed

Using an Insert Damaged threads before a repair © Goodheart-Willcox Co. , Inc. Installed insert

q An automotive technician must be able to remove broken bolts, screws, studs, and

q An automotive technician must be able to remove broken bolts, screws, studs, and fasteners having rusted or rounded -off heads q Certain tools and methods are needed for removing problem fasteners © Goodheart-Willcox Co. , Inc.

Removal Methods q Grasp a rusted or rounded head with locking pliers q Use

Removal Methods q Grasp a rusted or rounded head with locking pliers q Use a stud puller or stud wrench m removes studs and bolts broken off above the surface of the part © Goodheart-Willcox Co. , Inc.

Removal Methods q Cut a slot in the fastener with a hacksaw or weld

Removal Methods q Cut a slot in the fastener with a hacksaw or weld on a nut to grasp q Use a hammer and punch m angle the punch so that blows from the hammer can drive out the broken fastener q Drill a hole almost as large as the inside diameter of the threads m use a tap or punch to remove thread shell © Goodheart-Willcox Co. , Inc.

Removal Methods Using a screw extractor A. Drill a hole B. Tap the extractor

Removal Methods Using a screw extractor A. Drill a hole B. Tap the extractor into the hole C. Unscrew the extractor and bolt © Goodheart-Willcox Co. , Inc.

Removal Methods Use rust penetrant, a chemical that dissolves rust or corrosion © Goodheart-Willcox

Removal Methods Use rust penetrant, a chemical that dissolves rust or corrosion © Goodheart-Willcox Co. , Inc.

Used between parts to prevent leakage of engine oil, coolant, transmission oil, and other

Used between parts to prevent leakage of engine oil, coolant, transmission oil, and other fluids © Goodheart-Willcox Co. , Inc.

Gaskets q Soft, flexible material placed between parts to prevent leakage q Made of

Gaskets q Soft, flexible material placed between parts to prevent leakage q Made of fiber materials, rubber, neoprene (synthetic rubber), cork, treated paper, or thin steel q When parts are fastened together, the gasket material fills small gaps, dents, or scratches in the mating surfaces © Goodheart-Willcox Co. , Inc.

Gasket Rules q Inspect for leaks before disassembly q Be careful not to damage

Gasket Rules q Inspect for leaks before disassembly q Be careful not to damage mating surfaces while removing parts q Clean off old gaskets carefully q Wash and dry parts thoroughly q Compare the new gasket to the shape of the mating surface © Goodheart-Willcox Co. , Inc.

Gasket Rules q Use a sealer if specified q When assembling, start all bolts

Gasket Rules q Use a sealer if specified q When assembling, start all bolts by hand q Tighten fasteners in steps q Use a crisscross tightening pattern q Do not overtighten fasteners m apply only the specified torque © Goodheart-Willcox Co. , Inc.

Sealers Gaskets are often coated with a sealer to help prevent leakage and to

Sealers Gaskets are often coated with a sealer to help prevent leakage and to hold the gasket during assembly © Goodheart-Willcox Co. , Inc.

Types of Sealers © Goodheart-Willcox Co. , Inc.

Types of Sealers © Goodheart-Willcox Co. , Inc.

Form-in-Place Gaskets q Used instead of conventional fiber or rubber gaskets q Two common

Form-in-Place Gaskets q Used instead of conventional fiber or rubber gaskets q Two common types are: m room temperature vulcanizing (RTV) sealer m anaerobic sealer © Goodheart-Willcox Co. , Inc.

RTV Sealer q Also called silicone sealer q Dries in contact with air q

RTV Sealer q Also called silicone sealer q Dries in contact with air q Used to form a rubber-like gasket on thin, flexible flanges q Available in tubes, with a shelf life of one to two years © Goodheart-Willcox Co. , Inc.

RTV Sealer Commonly recommended where two different gaskets join © Goodheart-Willcox Co. , Inc.

RTV Sealer Commonly recommended where two different gaskets join © Goodheart-Willcox Co. , Inc.

Using RTV Sealer q Apply in a continuous bead that is approximately 1/8” (3

Using RTV Sealer q Apply in a continuous bead that is approximately 1/8” (3 mm) wide q Circle all mounting holes q Torque components in place while the RTV is still wet to the touch m within about 10 minutes © Goodheart-Willcox Co. , Inc.

Anaerobic Sealer q Cures to a plastic-like substance in the absence of air q

Anaerobic Sealer q Cures to a plastic-like substance in the absence of air q Designed for tightly fitting, thick parts q Used between two smooth, true surfaces © Goodheart-Willcox Co. , Inc.

Using Anaerobic Sealer q Apply in a continuous bead that is approximately 1/16”-3/32” (1.

Using Anaerobic Sealer q Apply in a continuous bead that is approximately 1/16”-3/32” (1. 5 mm-2 mm) wide q Circle all mounting holes q Torque components in place within 15 minutes of sealer application © Goodheart-Willcox Co. , Inc.

Using Sealers Anaerobic and RTV sealers are used on this water pump © Goodheart-Willcox

Using Sealers Anaerobic and RTV sealers are used on this water pump © Goodheart-Willcox Co. , Inc.

Seals q Prevent leakage between a stationary part and a moving part q Found

Seals q Prevent leakage between a stationary part and a moving part q Found in engines, transmissions, power steering units, and any part containing fluid and moving parts q Made of synthetic rubber molded onto a metal body © Goodheart-Willcox Co. , Inc.

Seal Application Seal lip faces the fluid and keeps it inside the part ©

Seal Application Seal lip faces the fluid and keeps it inside the part © Goodheart-Willcox Co. , Inc.

Seal Rules q Inspect the seal for leakage before disassembly m if the seal

Seal Rules q Inspect the seal for leakage before disassembly m if the seal is leaking, look for a bent shaft, misaligned seal housing, or damaged parts q Remove the old seal carefully, without scratching the seal housing © Goodheart-Willcox Co. , Inc.

Seal Rules Inspect shafts for wear and burrs © Goodheart-Willcox Co. , Inc.

Seal Rules Inspect shafts for wear and burrs © Goodheart-Willcox Co. , Inc.

Seal Rules q Compare the old seal to the new seal m make sure

Seal Rules q Compare the old seal to the new seal m make sure the inner and outer diameters match before installation q Install the new seal correctly m coat the outside with an approved sealer m coat the inner lip of the seal with system fluid m install the seal with the sealing lip toward the inside of the part © Goodheart-Willcox Co. , Inc.

O-Ring Seal q Stationary seal that fits into a groove between two parts q

O-Ring Seal q Stationary seal that fits into a groove between two parts q When the parts are assembled, the synthetic rubber seal is partially compressed to form a leakproof joint © Goodheart-Willcox Co. , Inc.

O-Ring Seal Normally, the O-ring seal is coated with system fluid before installation ©

O-Ring Seal Normally, the O-ring seal is coated with system fluid before installation © Goodheart-Willcox Co. , Inc.

Synthetic Seal Specially-shaped seal that fits down into a groove formed in the part

Synthetic Seal Specially-shaped seal that fits down into a groove formed in the part © Goodheart-Willcox Co. , Inc.