Service technology, tools and equipment of the workplace

Service Technology

There are several methods for performing vehicle maintenance and repair procedures, which the reader will find references in the text of this manual. Following them will make the work of a home mechanic more efficient, will allow the best organization and quality of various technical procedures and will be the key to a thorough and complete performance of all work.

Fasteners

Fasteners are nuts, bolts, studs and screws that are used to connect two or more parts together. There are a few things to keep in mind when working with fasteners. In almost any fastener, one or another type of locking and locking devices is used. These can be lock washers, locknuts, lock flags, or thread locking compound. All threaded fasteners used must be absolutely clean and straight, with undisturbed threads and non-rounded corners of the hex heads on which the wrench is put on. It should be a rule to replace damaged nuts and bolts with new ones. Special self-locking nuts with nylon or fiber inserts cannot be reused, as they lose their locking properties when released and must always be replaced with new ones during assembly.

Rusted bolts and nuts must be treated with a special penetrating compound before loosening and to avoid damage. Many mechanics prefer to use turpentine for this purpose, which is conveniently applied from a special small canister with a long spout. After wetting "stuck" fasteners with a penetrating composition, before proceeding with its release, the composition should be thoroughly impregnated with an oxidized contact layer for several minutes. Heavily rusted fasteners can be cut down with a chisel, cut down with a hacksaw or removed using a special wrench.


When cutting off a bolt head or breaking off a stud on an assembly, the rest of the threaded part can be drilled out or removed using a special tool. Most bodyshops can take on this as well as others (e.g. repairing stripped threads in threaded holes), repair procedures.

The flat washers and lock washers must always be reinstalled in the same order and in the same way as before when reassembling. Always replace damaged washers with new ones. Between lock washer and soft metal surface (e.g. aluminum), thin sheet metal or plastic, flat washers should always be installed.

Fastener dimensions

For many reasons, automotive manufacturers are increasingly adopting metric fasteners. However, it is important to know the difference between the sometimes used standard (also called American, or SAE standard) and more universal in the system of measures with metric fasteners, since, despite the external similarity, they are not interchangeable.

All bolts, both standard and metric, are classified by diameter, thread pitch and length. For example, a standard 1/2 - 13 x 1 bolt is half an inch in diameter, 13 threads per inch, and 1 inch long. Metric bolt M12 - 1.75 x 25 has a diameter of 12 mm, thread pitch 1.75 mm (distance between adjacent turns) and length 25 mm. Both bolts are externally almost identical, but are not interchangeable.

In addition to the features listed, both metric and standard bolts can be identified by looking at the head. To begin with, the distance between the flats of the head of a metric bolt is measured in mm, while for a standard bolt it is in inches (the same is true for nuts). As a consequence, a standard wrench is not suitable for use with metric fasteners, and vice versa. In addition, the heads of most standard bolts usually have radial notches that determine the maximum allowable tightening torque of the bolt (degree of strength). The more notches, the higher the allowable force (on cars, bolts with a degree of strength from 0 to 5 are usually used). The strength class of metric bolts is determined by a numerical code. Code numbers are usually cast, as for standard ones, on the bolt head (on vehicles, bolts of strength classes 8.8, 9.8, and 10.9 are usually used).

Strength class marking for standard hex nuts

3 points Strength class 5

6 points Strength class 8

Property class marking for metric hex nuts

Arabic 9 Strength class 9

Arabic 10 Strength class 10

Also, according to the marks of the strength class, standard nuts can be distinguished from metric ones. To identify the strength of standard nuts, dot marks are used, stamped on one of the end surfaces of the nut, while the marking of metric nuts is again done using numbers. The greater the number of points, or the higher the value of the digital code, the higher the allowable tightening torque of the nut.

Strength class marking for metric studs

The ends of metric studs are also marked according to their strength class. Large studs are marked with a digital code, while smaller ones are marked in the form of a geometric figure.

Dimensions / marking of the strength class of standard (SAE and USS) bolts

Dimensions/marking of the property class of metric bolts

It should be noted that a significant part of the fasteners, especially the strength class from 0 to 2, is not marked at all. In this case, the only way to distinguish a standard fastener from a metric fastener is to measure the thread pitch, or compare the thread with a uniquely identified one.

Standard fasteners are also often referred to as SAE fasteners, as opposed to metric fasteners, however, it should be remembered that only small fasteners fall under the SAE classification. Large fasteners with non-metric threads are American standard fasteners (USS).

Since fasteners of the same geometric size (both standard and metric) may have different strength classes, when replacing bolts, nuts and studs on a car, attention should be paid to the conformity of the strength class of the new fastener being installed with the strength class of the old one.

Procedure and procedure for tightening threaded connections

Most threaded connections should be tightened to the torques specified in the size and adjustment tables at the end of this manual (fastener tightening force is understood as the torque applied to it when tightening). Below, the tightening force will also be referred to as the fastener tightening torque. Over-tightening the fastener may break the integrity of the fastener, while under-tightening it leads to insecure connection of the mating components. Bolts, screws and studs, depending on the material from which they are made and the diameter of the threaded part, usually have strictly defined permissible tightening torques, many of which, as mentioned above, are listed in the tables of sizes and adjustments. Strictly adhere to the recommendations given for the tightening torques of the fasteners used on the vehicle. For tightening fasteners not mentioned in the Specifications, use the torque chart below. The values given in the table are based on fasteners of strength classes 2 and 3 (Higher grade fasteners allow for more tightening), in addition, it is understood that the tightening of the dry (with unlubricated thread) fasteners in steel or cast (not aluminum) detail.

Metric thread sizes
M—6	9 - 12 Nm
M—8	19 - 28 Nm
M—10	38 - 54 Nm
M—12	68 - 96 Nm
M—14	109 - 154 Nm

Pipe thread sizes
1/8	7 - 10 Nm
1/4	17 - 24 Nm
3/8	30 - 44 Nm
1/2	34 - 47 Nm
1/4 — 20	9 - 12 Nm
5/16 — 18	17 - 24 Nm
5/16 — 24	19 - 27 Nm
3/8 — 16	30 - 43 Nm
3/8 — 24	37 - 51 Nm
7/16 — 14	55 - 74 Nm
7/16 — 20	55 - 81 Nm
1/2 — 13	75 - 108 Nm

Fasteners located around the perimeter of any part (such as cylinder head bolts, oil pan and various covers), in order to avoid deformation of the part, it must be given and tightened in a strictly defined order. The procedure for tightening and retracting such fasteners is given in the relevant Chapters of the Guide. Unless a special procedure is specified, the following procedure should be followed to avoid distortion of the component. In the first stage, all bolts or nuts must be finger-tight. Further, each of them in turn must be tightened for another full turn, and the transition from one bolt / nut to another must be carried out in a diagonal order (criss-cross). Then, returning to the first bolt / nut, you should repeat the procedure in the same order, tightening the fasteners another half turn. Continue in the same manner, tightening each bolt/nut this time a quarter of a turn at a time until they are all tight. When giving away fasteners, you should also follow the described procedure, but in reverse order.

Disassembly of components

The disassembly of all components must be carried out in such a manner that during assembly each part can be installed in its original place and in the correct way. Remember the characteristic features of the appearance, if necessary, make landing marking of parts that can be installed in place in an ambiguous way (such elements include, for example, a thrust washer fitted with a groove on the shaft). It's a good idea to arrange the removed parts on a clean work surface in the order in which they were removed. It will also be useful to draw up simple schematic sketches or take step-by-step photographs of the component to be dismantled.

When removing a fastener, try to mark its original position on the assembly. Often, immediately reinstalling fasteners and washers after removal of the corresponding part avoids confusion during assembly. If this is not possible, all fasteners should be placed in a box specially prepared for this purpose, divided into sections and marked accordingly, or simply in separate marked boxes. This course of action is especially useful when dealing with components that consist of many small parts, such as a carburetor, alternator, valve train, instrument panel, or trim elements.

When disconnecting electrical contacts and connectors, attention should be paid to marking wires or harnesses using insulating tape with a numerical or letter code applied to it.

Sealing surfaces

On all vehicles, gaskets are used to seal the junction of the mating surfaces of two or more parts and serve to prevent leakage of oils and fluids and maintain high pressure or vacuum inside the assembly.

Often these gaskets are coated with a liquid or paste sealing compound prior to installation. Often, under the influence of time, temperatures or pressure, such a strong "sticking" to each other mating surfaces that the separation of parts becomes a difficult task. In many cases, the dismantling of such assemblies is helped by tapping them from the outside along the perimeter of the junction with a soft-faced hammer. You can also use an ordinary hammer for this purpose, striking through a wooden or plastic spacer. Cast housings and fragile components should not be tapped. When this kind of problem occurs, always check that all fasteners have been removed first.

Avoid using a screwdriver or pry bar to separate parts by inserting them between the mating surfaces, as the sealing surfaces can easily be damaged, which can cause leaks in the future. If jerking "stuck" assembly elements cannot be avoided, use a pen from the old mark for this purpose, but remember that after that all the chips that have formed must be carefully removed from the mating surfaces and from the inside of the assembly.

After separating the parts, their mating surfaces must be carefully cleaned, scraping off traces of the old gasket material. Hardened fragments of the old gasket can be pre-softened with a rust converter or a special chemical composition, and then removed from the mating surface with a scraper. In this case, a piece of copper tube with a flattened and pointed end can be used as a scraper. The use of copper tubing for this purpose is recommended, since copper is usually softer than materials used in a car, which reduces the risk of damage to the mating surface. Some gaskets can be easily removed with a copper brush, however, regardless of the method used, the mating surfaces should be completely clean and smooth. If for any reason the mating surface is scratched, fill the scratch with gasket sealant before assembling the components. In most cases, you should use a non-curing (or semi-hardening) sealant.

Hose Removal Tips

Attention! If your vehicle is equipped with an air conditioning system, never disconnect any hoses from the air conditioning components until the system has been discharged by the vehicle manufacturer's dealer or by an air conditioning specialist at a car repair shop.

The precautions to be followed when removing hoses are very similar to those when removing gaskets. Avoid damage to the surfaces of the fittings and pipes on which the hoses are put on, as this can cause leaks. In particular, this applies to the procedure for removing the radiator hoses. Due to various chemical reactions, "sticking" rubber hoses to the mating surfaces of fittings and branch pipes. To remove the hose, first of all, loosen the clamp securing it to the fitting. Then grab the hose close to the clamp with tongs with a sliding joint and begin to rotate it on the fitting / connecting pipe from right to left. Continue this procedure until the hose is completely free, then remove the hose from the fitting. A small amount of silicone or other lubricant will make the procedure easier if it can be injected into the gap between the fitting and the hose. To facilitate the installation of the hose, grease the inside of the hose and the outside of the fitting.

As a last resort, or if it is absolutely necessary to replace the hose with a new one, the end of the removal hose put on the fitting can be cut with a knife and then separated from the surface of the fitting. At the same time, try not to damage the metal of the fitting / under the connecting pipe with a knife.

If the hose clamp is damaged, replace it with a new one. Twist-type clamps tend to loosen over time, so regardless of their condition, it is best to replace them with screw-type clamps on occasion.

Tool

The choice of a good tool is one of the basic requirements for anyone who plans to perform car maintenance or repair procedures on their own. At first glance, the costs associated with acquiring the required set of tools may seem too high, but when compared with the costs associated with the performance of routine maintenance procedures and the simplest car repairs at a service station, they turn out to be quite reasonable.

To assist the average car enthusiast in choosing the right tool for the various car care procedures described in this manual, below are lists of three tool kits, tentatively titled: Routine Maintenance and Minor Repair Tool Kit; a set of tools for general and major repairs and a special tool. Vehicle owners with no practical experience in mechanical work should start by performing procedures limited to the use of tools from the first list, while improving their skills and gradually expanding the range of tools used. As you gain experience, you can move on to more complex tasks, complementing the set of tools at hand. After some time, the acquired skills will allow you to start performing more complex work that requires the use of a tool from the second list (for general and major car repairs). When your qualifications begin to allow you to save significant funds on the independent implementation of complex repair procedures, you can consider purchasing a special tool.

A set of tools for routine maintenance and minimal car repairs

The list below includes the minimum tools required to perform routine maintenance and minor vehicle repairs. It is recommended to purchase a set of combination wrenches (with a regular open end on one end and a flare on the other), despite the high cost of such a kit compared to the cost of a set of conventional wrenches, the costs will be justified, because. these keys have the benefits of both types.

• combination wrench set (1/4 - 1 inch; 6 - 19 mm)
• adjustable wrench
• candle key (with rubber insert)
• Gap adjustment tool
• Probe set
• Nipple wrench for bleeding brakes
• Screwdrivers:
• with a flat sting (150 mm long and 8 mm in diameter)
• With a cross sting (No. 2 x 6 inches (150mm long)
• Combination pliers
• Hacksaw with a set of blades
• Tire pressure gauge
• Grease gun (syringe)
• oil canister
• Fine sandpaper
• Wire brush
• Tool for stripping terminals and battery wire contacts
• Oil filter wrench
• Funnel (medium size)
• Supports for fixing the car in a raised position (2)
• Drainage tank

Note. If routine maintenance includes basic adjustments, you will also need to purchase a good quality strobe light and a combined tachometer/breaker closed time instrument. Although these tools are included in the list of special tools, they are mentioned here because they are absolutely necessary for proper engine ignition tuning, which is part of the vehicle's routine maintenance procedures.

A set of tools for general and overhaul of a car

This tool is necessary when carrying out any car engine repair operations and is offered in addition to the first list. This listing includes a complete set of interchangeable sockets. At a significant cost, a set of interchangeable heads brings invaluable benefits due to its versatility and ease of use - especially in combination with the various types of actuators included in the kit. It is recommended to use 1/2" drives preferably (not 3/8 inch), because they, although more expensive, can be used with almost any type of torque wrench (Ideally, a good mechanic should have both types of drives at his disposal). A cheaper alternative to a set of interchangeable sockets is a set of tubular wrenches.

• Set of interchangeable sockets (including type heads "Torx") (or tubular wrenches), sizes corresponding to the sizes of wrenches from the previous list
• Ratchet reversible drive (for use with interchangeable sockets)
• Gate length 250 mm
• Universal (gimbal type) hinge (for use with sockets)
• torque wrench (with drive of the same size as for interchangeable sockets)
• Round Face Hammer - 8 oz (about 230 g)
• Soft-faced hammer (plastic or rubber) (mallet)
• Screwdrivers:
• with a flat sting (150 mm long and about 6.5 mm in diameter)
• with a flat sting (strong No. 2, 8 mm)
• With a cross sting (No. 3 x 8 inches (203 mm))
• With a cross sting (strong No. 2)
• Clamping pliers
• Pliers:
• For electricians (with insulated handles)
• narrow-nosed (needle nose pliers)
• For retaining rings (internal and external)
• Chisel - 1/2 inch (13 mm)
• Scraper (made of flattened and pointed at one end of a copper tube)
• scriber (scriber)
• Kerner
• Beards with a thin sting (1.6, 3.2, 4.8mm)
• Steel Ruler / Flatness Gauge
• Allen key set (for heads with internal hexagon)
• File set
• Wire brush (big)
• Second set of supports
• Jack (hydraulic or scissor type)

Note. Another tool in constant demand is a 3/8" chuck electric drill (up to 9.5 mm) with a set of good quality drill bits.

Special tool

This list includes tools that are quite expensive, are not required regularly, or require the manufacturer's instructions to be followed when using. If your area of activity does not include the frequent performance of complex mechanical operations, the acquisition of such a tool will be a bad investment. It is reasonable to buy it in clubbing with friends or rent it in car service workshops.

The list includes only those tools that can be found in retail trade or which are produced for distribution to the dealer offices of firms. Sometimes in the text of the Manual you will find references to such special tools. Usually, the authors try in parallel to propose an alternative method that avoids the obligatory use of a hard-to-reach tool. If it is impossible to avoid the use of a special tool, and acquiring it for use is problematic, it is better to entrust the performance of the relevant work to car service specialists.

• Valve spring compression tool
• Piston ring cleaner
• Piston ring crimping tool
• Piston ring installer
• Cylinder Compression Gauge (compressometer)
• Countersink for processing the edges of cylinders
• Hone for processing cylinder mirrors
• Cylinder diameter gauge
• Micrometer (micrometers) and/or dial caliper
• Hydraulic tappet removal tool
• ball joint separator
• Universal type puller
• impact screwdriver
• Dial meter set
• stroboscope (with inductive sensor)
• Manual combination pump (vacuum/pressure)
• Tachometer/instrument for measuring the duration of the closed state of the contacts of the breaker
• Universal tester for electrical measurements
• lifting rigging
• Brake spring removal/installation tool
• floor jack

Purchasing a tool

A novice mechanic in terms of acquiring the necessary tools for performing routine maintenance and repair of a car can be offered several practical tips. When preparing for routine maintenance or minor vehicle repairs, it is wise to purchase the tool separately. On the other hand, in the case of planning extensive work, it is easier and more reliable to buy a set of modern tools in a retail store. Purchasing a kit usually costs somewhat less than individual purchases and is often supplemented with an attached tool box. In the future, to expand the choice, individual tools, additional kits and a larger tool box can be purchased. The gradual expansion of the set of tools will allow you to stretch the costs and decide on the choice of really necessary tools.

Specialized tool magazines are the only source for some specialty tools, but whatever the source, avoid cheap purchases, especially for screwdrivers and replacement sockets, as they will likely not last long. As a result, the costs associated with the replacement and restoration of a cheap tool will be incomparably more significant than the costs of a one-time purchase of a quality product.

Tool care and storage

A good tool is a valuable investment, so it is wise to take care to keep it clean and ready for use at all times. After using the tool, always thoroughly wipe the surface with a clean, dry cloth before storing it to remove any dirt, grease, and metal particles. Never leave tools scattered around the work area. After completing the work, carefully check the area under the hood and under the car for the presence of a forgotten tool.

For storing tools such as screwdrivers, pliers, hammers, etc. a tool comb mounted in a convenient location on the garage wall is ideal. Sets of wrenches and interchangeable sockets should be stored in metal boxes. The measuring tool must be stored in a dry and clean place inaccessible to corrosion.

You should always pay attention to the condition of the working surfaces of the tool. The impact part of the hammer head is subject to riveting during operation, screwdrivers lose sharpening of their stings over time. Don't be stingy with taking a little time and attention to use sandpaper or a file to remove rivets and tidy up the cutting edges. Replace irreparably worn or damaged tools.

With careful care, the tool will serve you faithfully for a very long time.

Workplace equipment

Speaking about the tool, it is impossible not to mention the equipment of the workplace. If more serious work is to be done than simple maintenance, care should be taken to prepare a suitable work site.

We have to admit that many motorists are forced to remove the engine and other similar work far from being in a garage or workshop. However, in any case, an important requirement is the presence of a roof or awning.

Whenever possible, any procedures for disassembling parts of vehicle systems should be carried out on a clean, flat workbench, or a sturdy table at a convenient height. The workbench must be equipped with a vise. Sufficient is the presence of a vise with a jaw opening of up to 100 mm and with soft pads on the jaws.

As mentioned above, the work site must be equipped with a clean, dry place for storing tools, lubricants and cleaning fluids, fillers, paints and varnishes, etc.

It should be noted that an absolutely necessary tool is an electric drill, therefore, the work site must be equipped with a power source to connect it. The presence of a drill with a chuck up to 9.5 mm and a set of high-quality drills will greatly facilitate many procedures.

Finally, the workplace should always have an adequate supply of old newspapers and clean, lint-free rags for cleaning the work area, tools, and vehicle parts.

Waste should be handed over to recycling centers in sealed containers.

Never do any work on the bare painted surface of the car, use protective fender pads, or, at worst, cover the polished surfaces with old blankets.