Runout- amplitude of deviation of the shaft shank from the axis.
Liner - part of the bushing placed in the cylinder as a friction bearing surface for the shaft, piston pin, etc. Bushings are generally replaceable parts.
Surface development - presence of scratches or grooves on the surface. The cylinder wall may become worn out due to the presence of abrasive particles that are moved up and down by the piston rings.
Bearing projection - excessive height of the liners, which ensures a tight fit of the back side of the bearing to the bed after engine assembly.
Gas distribution mechanism - the engine valve mechanism, which includes parts from the camshaft to the valves.
Galtovka- removal of burrs from the working surfaces of the bearing.
Sleeve- a replaceable bushing pressed into the engine block. The inner surface of the liner is the cylinder wall.
Damper- a cylindrical counterweight located in front of the crankshaft. The damper is a damper of torsional vibrations of the shaft caused by the action of the pistons.
Detonation- a process that occurs when the ignition and gas distribution phases are mismatched and manifests itself as a metallic knock.
Iron blue - blue pigment, which is used to determine the contact area of elements. Used to determine the width and location of the valve head to seat contact.
Stub- a soft metal plug that is installed in the hole in the engine cooling jacket.
Badasses- type of wear caused by the movement of material of rubbing parts. Appears as small pits or grooves on the surface.
Gap- the space between two elements. Sometimes defined as the distance a gear can move without moving the gear it meshes with.
Gap- the distance between parts of the same group, for example, between the teeth of a gear transmission or between a pusher and a valve stem.
Rounding- transverse or oblique bevel of the sharp edge of the part
Replacing rings - a procedure that includes replacing piston rings and treating the cylinder walls.
Cylinder mirror - extremely smooth surface of the cylinder wall.
The combustion chamber - the space between the piston located at TDC and the inner surface of the cylinder head, where combustion of the air-fuel mixture occurs.
Piston groove - a groove in the piston head where the ring fits.
Major renovation - a complex event, including disassembling the unit, cleaning and inspecting its parts, the necessary replacement or restoration of elements, assembling the entire unit and making adjustments.
Carter- the lower part of the engine in which the crankshaft is installed. The crankcase includes the lower part of the cylinder block and the engine sump.
Crankshaft - the main engine shaft located in the crankcase. The crankshaft has journals to which connecting rods are connected. This shaft converts the linear movement of the pistons into rotation.
Complex project - disassembling and reassembling the engine to exacting specifications.
Taper- a gradual change in diameter along the axis of the shaft or hole. In a cylinder, taper is the result of uneven wear, which occurs more at the top than at the bottom.
Main bearing - a babbitt plain bearing on which the crankshaft rests.
Crank- an eccentric element of the crankshaft to which the connecting rod is connected.
Crank- the crankshaft element to which the connecting rod is connected.
Crank group - machined or rebuilt crankshaft with new main and connecting rod bearings.
Main bearing cap - a cast iron cover that is bolted to the bottom of the cylinder block and supports the main bearing.
Bearing caps - covers secured with bolts or nuts that form the bearing surface of plain bearings or liners.
Highway- a capacious cavity in the cylinder block through which oil is supplied to lubricate moving parts.
Oil deflector- a screen located near the valve stem to reject oil.
Oil scraper ring - lower piston ring. Several oil rings can be installed on the piston. This ring serves to remove excess oil from the cylinder wall as the piston moves.
Oil gap - space for lubricant to reach the rubbing elements (shaft journals and liners).
Compression ring mark - a small dot or other mark that is located on the upper side of the compression ring.
Tap- a tool for cutting threads in a hole.
Mechanical restoration - a process that involves removing metal from the surface being processed by cutting.
N.D. - outside diameter.
Nagar- soft or hard black deposits that accumulate in the combustion chamber, on spark plugs, under rings and on valve heads.
Run-in- the period of operation during which grinding and shrinkage of the mating surfaces of new or restored parts occurs. During the break-in period, it is prescribed to operate the car in a gentle manner for a certain mileage.
Support bearing - a small bearing located in the center of the flywheel (or in the rear shank of the crankshaft), which includes the front shank of the transmission secondary shaft.
Axial play - the distance over which the installed shaft can move in the longitudinal direction.
Engine base - a term used to designate the cylinder block, crankshaft, main bearings and connecting rod lower heads as elements of the same group.
Bridge between grooves - part of the piston located between the grooves of the piston rings.
Plastic indicator - a flat strip of plastic material that is used when measuring the oil clearance of a plain bearing. The indicator strips are laid on the shaft journals, after which the bearing caps are installed and tightened with bolts. Then the covers are removed, and based on the thickness of the crushed strips, using a conversion table, the size of the oil gap of the sliding bearing is determined.
Processing surface - the surface of the part from which material is removed during machining.
Error- deviation of the result obtained during measurement from the actual value.
Repair size bearings - bearings of smaller diameter installed on a re-ground crankshaft.
Piston- a cylindrical part of the engine that is connected to the connecting rod. The piston moves in the cylinder. and under the pressure of the burning air-fuel mixture, it imparts movement to the crankshaft through the connecting rod.
Piston ring - a ring located in the piston groove and in contact with the cylinder wall. The rings serve to create a seal between the piston and cylinder and also to remove excess oil from the cylinder wall. In accordance with their purpose, compression and oil scraper rings are distinguished.
Piston pin - a cylindrical, usually hollow pin that passes through the piston and attaches it to the upper head of the connecting rod.
Bearing bed - upper bearing surface of the main bearing.
Press fit - a tight fit created by the diameter of the shaft exceeding the diameter of the hole.
Valve lapping - abrasive treatment of the chamfer and valve seat, resulting in a gas-tight connection.
Wire liner - a repair part used to restore a damaged or worn threaded connection. The insert is installed in the bored hole and forms a thread of the required smaller diameter.
Run- restoration of threads with a tap or die.
Scan- a device with grooved cutting edges designed for processing cylinder walls.
Camshaft- an engine shaft having cams to drive the valve mechanism. Driven by a toothed belt or chain through a sprocket or gear.
Boring- mechanical surface treatment performed to increase the size of the cylinder. A boring bar is used for cutting.
Cooling jacket - the cavity around the cylinders, which is located between the shells of the cylinder block or its head. Coolant circulates in the jacket.
Stuffing box- a sealing element that serves to prevent oil leakage. As a rule, it is a dynamic seal placed on the shank of a rotating shaft.
Free height- height of the spring in the unloaded state.
Free movement - the distance the lever or pedal moves before the mechanism is activated.
Segment key - key with rounded back side (the curve is visible from the side).
Saddle- the surface on which the part rests. For example, the valve seat is the surface on which the valve head rests.
Static balance - balance of elements at rest.
Compression ratio - the relationship between cylinder volumes when the piston is at TDC and BDC
Knock of bearings - the sound produced when the elements of a damaged or worn bearing rotate.
Step- type of wear that appears on the lower part of the bridge between the grooves of the piston rings. The height of the step determines the lateral play of the rings. The length of the step from the back wall of the groove determines the clearance of the back side of the rings.
Crackers- a composite fastener that holds the spring retainer to the valve stem.
Tact- movement of the piston from BDC to TDC or its path in the opposite direction.
Pusher- a part located between the camshaft cam and the valve stem or rocker arm.
Sealing ring - a ring-shaped sealing element made of appropriate rubber material. The ring is pressed into the groove to seal the connection.
Thrust washer - a washer made of bronze or hardened steel, installed between two moving elements to limit their longitudinal movement.
Thrust bearing - a main bearing having a thrust surface, due to which the axial play of the crankshaft is limited.
Truncated block - a replaceable cylinder block assembled with a crankshaft, pistons and, as a rule, a camshaft.
Material fatigue - destruction of the material under the influence of cyclic loads. It appears in the form of cracks, along which the part soon collapses.
Installation height - height of the spring, measured in the installed state. For example, the distance from the seat to the back of the valve spring retainer.
Hon- a tool driven by an electric motor and used to remove glassy film from cylinder walls when replacing piston rings.
Cylinder- an engine cylinder or other cylindrical hole made in a housing part. The term is used to describe the process of boring or other machining using cutting tools. The diameter of the cylinder is equal to the diameter of the main hole.
Cast iron- an alloy containing steel and at least 2% carbon compounds. Cylinder heads and blocks are made of cast iron. This is due to the fact that this material is relatively cheap, and also because it is suitable for the manufacture of cast parts.
connecting rod- a rod connecting the crankshaft crank to the piston.
Connecting rod cover - a part of the connecting rod with which it is attached to the crank pin.
Neck- part of the shaft that is located in the bearing.
Hairpin- a metal rod with threads at both ends.
Key- a small metal part that is inserted into the grooves of two connected parts. If the gear has a keyed fit on the shaft, then the presence of the key prevents the elements from turning relative to each other.
Gap gauge - a thin metal strip with engraved thickness. Used to determine the size of the gap by comparison.
Piston skirt - part of the piston located under the rings and pin holes.