Mating surfaces and gaskets
When disassembling mating parts, never insert a screwdriver or any similar tool between the mating surfaces. This can lead to serious damage which, after reassembly, results in leakage of oil, coolant, etc. Separation is usually done by tapping around the perimeter of the mating surfaces with a hammer made of soft material, which allows the gasket to be separated. However, it should be borne in mind that this method is not suitable for disassembling joints in which dowel pins are used to align the relative position of the parts to be joined.
If a gasket is required between the mating surfaces of two parts, a new gasket should always be installed during assembly. The gasket to be installed must be dry unless otherwise specified in the assembly manual. Before installation, make sure that the mating surfaces are clean and dry and that there are no traces of the old gasket on them. When cleaning the mating surfaces, use a tool that does not degrade the surface finish and remove any burrs or nicks with an oil-filled abrasive stick or fine file.
Make sure that all threaded connections are clean and do not allow locking compound to get into them, unless otherwise specified in the assembly instructions.
Make sure all openings, channels or pipes are clean and blow out with compressed air.
Sealing cuffs
The cuff can be removed by prying it out with a wide-end screwdriver or similar tool. For the same purpose, you can screw several self-tapping screws into the cuff and pull out the cuff using pliers or another similar tool.
The removed cuff in any case and regardless of the reason for the removal should be replaced with a new one during installation.
The very thin sealing lip of the collar can be easily damaged and will not perform its function unless dirt, scratches, nicks or grooves are completely removed from the surface it contacts. If the surface of the part cannot be restored and the manufacturer has not provided for some movement of the seal relative to the surface, the part must be replaced.
In order not to damage the sealing lips of the collar, protect them from contact with any parts during installation. If possible, use adhesive tape or a conical mandrel. Lubricate the cuff with oil before installation. When installing a double lip seal, fill the space between the lip seals with grease.
Unless otherwise specified, when installing the seal, its sealing lips must face the direction of the lubricant, the leakage of which they prevent.
To press the cuff, use a piece of pipe of the appropriate diameter with machined ends or a wooden block, and if the cuff seat is equipped with a shoulder, the cuff should be installed all the way into this shoulder. If the seat does not have a shoulder, the collar must be installed flush with the outer surface of the housing in which it is installed (unless otherwise specified).
Threaded connections
Nuts, bolts and screws are parts where corrosion usually occurs. If the threaded connection does not loosen, moisten the connection point with penetrating oil, kerosene or similar liquid and leave it for a while. You can try using a screwdriver or impact wrench. If none of these methods help, you can try warming up the connection gently. If this does not help, then you will have to use a hacksaw or chisel.
Studs are usually turned out as follows. Thread two nuts onto the stud, one next to the other, and tighten them together. Then, turning the lower nut with a wrench, unscrew the stud. Studs or bolts that have broken below the surface of the part they are screwed into can sometimes be removed with a stud extractor. Before driving a stud or bolt into a blind hole, first make sure that that the hole is completely free of oil, grease, water or other liquid. If this is not done, the housing may be destroyed due to the hydraulic pressure that occurs when the bolt or stud is screwed in. When tightening the castle nut, tighten the nut to the prescribed torque, and then tighten to the nearest cotter pin hole. Never loosen the nut to align the pin holes unless specifically directed to do so in the assembly instructions.
If it is necessary to check the correct tightening of a bolt or nut, unscrew it (her) a quarter turn, then tighten again to the required torque. However, this must not be done if the fastener was still turned to the required angle after tightening with a torque wrench.
For some threaded connections, especially for cylinder head bolts or nuts, the last stage of tightening is not indicated by the torque, but by the angle by which the fastener must be tightened. Usually, a relatively small tightening torque is indicated for screwing in the bolts in a certain sequence, and then additional rotation is performed in one or more steps at the specified angles.
Locknuts, washers and other means against self-unscrewing
A washer must always be installed under any fastener that will rotate relative to the part or housing when tightened.
Spring washers or split washers in critical connections, such as the bottom end of the connecting rod, should always be replaced. Folding washers, if they have been bent at least once to release a nut or bolt, should also always be replaced.
Self-locking nuts can be used repeatedly in non-critical connections if resistance is felt when tightening when the locking part of the nut comes into the thread of the stud or bolt. However, it should be noted that with prolonged use, self-locking nuts gradually lose their effectiveness and must also be replaced periodically.
Cotter pins should always be replaced with new ones that match the size of the hole.
If an anti-loose compound has been applied to the threads, it must be removed with a wire brush and thinner, and fresh compound applied upon reassembly.
Special tools or fixtures
Some of the repair procedures described in this manual require the use of special tools and attachments such as a press, two or three jaw pullers, spring compressors, etc. Wherever possible, attachments are described that can replace the special tools provided by the manufacturers. In some cases, when an alternative is excluded, it is necessary to resort to the use of a proprietary special tool. This is done for safety reasons, as well as for efficient repairs. If your skills are not very high, or if you have not reached a full understanding of the procedures described, never try to do without using a special tool (fixtures), if the description of the procedure provides for its use. You can not only get injured, but also damage expensive parts.
Environment protection
When changing oils, brake fluid, antifreeze, etc., measures must be taken to prevent environmental pollution. For example, do not pour any of these liquids into public sewers or onto the ground. There are many collection points for used oils and other liquids. Each garage or secure parking area should have a special collection container for such liquids.
Due to the ever-increasing tightening of legislation requirements to reduce air pollution from motor vehicles, many modern cars are equipped with means that prevent insufficiently qualified persons from accessing the most important fuel system adjustments. These protective measures are primarily designed to prevent such persons from adjusting air/fuel mixtures, which could cause an increase in exhaust emissions. Such protective devices must be reinstalled after repair, in accordance with the manufacturer's requirements or current legislation.
Note. Drinking oil down the drain is illegal and immoral. Find your nearest used oil collection point.