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Repair of 4-cylinder engine BMW 3 Series E21
Main technical characteristics
The four-stroke, four-cylinder, in-line engine is mounted along the longitudinal axis of the vehicle at an angle of 30°. The engine uses a valve timing...
The four-stroke, four-cylinder, in-line engine is mounted along the longitudinal axis of the vehicle at an angle of 30°. The engine uses a valve timing...
Cylinder head characteristics
The cylinder head is cast from aluminum alloy. The head has three-spherical combustion chambers. The valve seats and guide bushings are pressed into the...
The cylinder head is cast from aluminum alloy. The head has three-spherical combustion chambers. The valve seats and guide bushings are pressed into the...
Cylinder Block Characteristics
The cylinder block is cast from a special grey cast iron and is integral with the cylinders. Cylinder diameters Ovality and taper of cylinder mirrors, mm, no...
The cylinder block is cast from a special grey cast iron and is integral with the cylinders. Cylinder diameters Ovality and taper of cylinder mirrors, mm, no...
Characteristics of the crank mechanism
Pistons The pistons are cast from aluminum alloy. Depending on the engine model, the piston bottoms can be flat or convex. Piston brand: Mahle, Karl Schmidt...
Pistons The pistons are cast from aluminum alloy. Depending on the engine model, the piston bottoms can be flat or convex. Piston brand: Mahle, Karl Schmidt...
Characteristics of the valve timing mechanism
The engine uses a valve timing mechanism with an overhead camshaft, the drive of which is carried out by a double-row roller chain. The chain tension is...
The engine uses a valve timing mechanism with an overhead camshaft, the drive of which is carried out by a double-row roller chain. The chain tension is...
Tightening torques for main threaded connections
Tightening torques for threaded connections, kgf·m Cylinder head bolts on a cold engine: 1st step: 3.4-4.4; 2nd reception: 6.7-7.1; 3rd reception: 7.7-8.1;...
Tightening torques for threaded connections, kgf·m Cylinder head bolts on a cold engine: 1st step: 3.4-4.4; 2nd reception: 6.7-7.1; 3rd reception: 7.7-8.1;...
Adjusting clearances in the valve drive mechanism
The clearances in the valve drive mechanism are adjusted by turning the rocker arm adjusting eccentric, after first loosening the lock nut. Adjustment of...
The clearances in the valve drive mechanism are adjusted by turning the rocker arm adjusting eccentric, after first loosening the lock nut. Adjustment of...
Removal the cylinder head
Remove the air filter. Disconnect the wires from the battery terminals. Disconnect the radiator drain hose and drain the coolant. Disconnect the cooling system...
Remove the air filter. Disconnect the wires from the battery terminals. Disconnect the radiator drain hose and drain the coolant. Disconnect the cooling system...
Disassembling the cylinder head
Cylinder head details: 1 - cylinder head; 2 - cylinder head gasket; 3 - cylinder head cover; 4 - cylinder head cover gasket; 5 — breather; 6 - valve guide...
Cylinder head details: 1 - cylinder head; 2 - cylinder head gasket; 3 - cylinder head cover; 4 - cylinder head cover gasket; 5 — breather; 6 - valve guide...
Cylinder head repair
Replacing valve guide bushings If the valve guides are excessively worn (for wear limits, see subsection " Detailed technical specifications "), replace the...
Replacing valve guide bushings If the valve guides are excessively worn (for wear limits, see subsection " Detailed technical specifications "), replace the...
Cylinder head assembly
Clean and check the condition of the parts thoroughly. The cylinder head is assembled in the reverse order of disassembly, taking into account the following:...
Clean and check the condition of the parts thoroughly. The cylinder head is assembled in the reverse order of disassembly, taking into account the following:...
Installing the cylinder head
After cleaning the mating surface of the cylinder block, check the protrusion of the mounting pins above its plane, which should not exceed 5 mm. Make sure...
After cleaning the mating surface of the cylinder block, check the protrusion of the mounting pins above its plane, which should not exceed 5 mm. Make sure...
Removal and installation the engine
Removal Remove the gearbox. Remove the engine cooling system radiator. Disconnect the wire from the "-" terminal of the battery. On vehicles with power...
Removal Remove the gearbox. Remove the engine cooling system radiator. Disconnect the wire from the "-" terminal of the battery. On vehicles with power...
Cylinder Block Parts
Cylinder block details: 1 — cylinder block; 2 - plugs; 3 — crankshaft rear oil seal holder; 4 - gasket; 5 - spacer washer; 6 — rear crankshaft oil seal; 7 —...
Cylinder block details: 1 — cylinder block; 2 - plugs; 3 — crankshaft rear oil seal holder; 4 - gasket; 5 - spacer washer; 6 — rear crankshaft oil seal; 7 —...
Crank mechanism parts
Crank mechanism parts: A - engines of all models of cars except "320" and "320i"; B - engines of cars of the models "320" and "320i" 1 — crankshaft; 2 —...
Crank mechanism parts: A - engines of all models of cars except "320" and "320i"; B - engines of cars of the models "320" and "320i" 1 — crankshaft; 2 —...
Disassembling the engine
Place the washed and cleaned engine on a rotating stand for disassembly. Remove the cylinder head as described above. Remove the protective cover and exhaust...
Place the washed and cleaned engine on a rotating stand for disassembly. Remove the cylinder head as described above. Remove the protective cover and exhaust...
Disassembling the connecting rod and piston group
The piston pins rotate freely in the upper head of the connecting rod and the piston bosses. The pin is held in the piston bosses from longitudinal movement by...
The piston pins rotate freely in the upper head of the connecting rod and the piston bosses. The pin is held in the piston bosses from longitudinal movement by...
Checking the technical condition of connecting rod and piston group parts
Make sure that the connecting rods are in the same weight group: connecting rods without bearing shells should not differ from each other in weight by more...
Make sure that the connecting rods are in the same weight group: connecting rods without bearing shells should not differ from each other in weight by more...
Installing the crankshaft
Make sure that the crankshaft main bearing journals and shells are of the same size group. Color codes (red or blue) on the main bearing shells must be...
Make sure that the crankshaft main bearing journals and shells are of the same size group. Color codes (red or blue) on the main bearing shells must be...
Replacing the centering bearing with grooves of the primary shaft of the gearbox
Press out the bearing with the protective washer, felt ring and protective cover from the crankshaft flange socket using the Kikko puller. Thoroughly clean and...
Press out the bearing with the protective washer, felt ring and protective cover from the crankshaft flange socket using the Kikko puller. Thoroughly clean and...
Replacing the needle bearing
Use a puller to press the bearing out of the crankshaft flange seat. Thoroughly clean and blow out the bearing seat in the crankshaft flange with compressed...
Use a puller to press the bearing out of the crankshaft flange seat. Thoroughly clean and blow out the bearing seat in the crankshaft flange with compressed...
Replacing the flywheel toothed rim
Check the condition of the flywheel toothed rim and, if the teeth are significantly worn, replace the toothed rim. Drill a hole about 8mm deep into the rim...
Check the condition of the flywheel toothed rim and, if the teeth are significantly worn, replace the toothed rim. Drill a hole about 8mm deep into the rim...
Grinding the flywheel
The plane of contact of the driven clutch disk on the flywheel must be smooth, without scratches and gaps. The scratches and gaps are removed by grinding....
The plane of contact of the driven clutch disk on the flywheel must be smooth, without scratches and gaps. The scratches and gaps are removed by grinding....
Checking the clearance between the bearing shells and the main journals of the crankshaft
Install the ungreased lower main bearing shells into the cylinder block seats (axial fixation of the crankshaft is provided by liners with cheeks of the middle...
Install the ungreased lower main bearing shells into the cylinder block seats (axial fixation of the crankshaft is provided by liners with cheeks of the middle...
Checking the axial clearance of the crankshaft
Install the crankshaft rear oil seal retainer with a new gasket. Install the flywheel onto the crankshaft. Lock the flywheel with a locking pin and tighten the...
Install the crankshaft rear oil seal retainer with a new gasket. Install the flywheel onto the crankshaft. Lock the flywheel with a locking pin and tighten the...
Checking the clearance between the bearings and the connecting rod journals of the crankshaft
Insert the pistons into the cylinders (without piston rings) with connecting rods in accordance with the cylinder number marks on the piston bottom (the count...
Insert the pistons into the cylinders (without piston rings) with connecting rods in accordance with the cylinder number marks on the piston bottom (the count...
Installing the camshaft drive
Place the pulley on the crankshaft nose without tightening the pulley mounting nut. Set the piston of the 1st cylinder to the TDC position at the end of the...
Place the pulley on the crankshaft nose without tightening the pulley mounting nut. Set the piston of the 1st cylinder to the TDC position at the end of the...
Timing mechanism parts
Details of the valve timing mechanism: 1 — timing mechanism covers; 2 - mounting sleeve; 3 - timing mechanism cover gaskets; 4 — front crankshaft oil seal; 5 —...
Details of the valve timing mechanism: 1 — timing mechanism covers; 2 - mounting sleeve; 3 - timing mechanism cover gaskets; 4 — front crankshaft oil seal; 5 —...
Adjusting the tension of the drive belts and the power steering pump
The normal deflection when pressing with the thumb on the branch between the alternator and fan pulleys for the alternator drive belt and when pressing with...
The normal deflection when pressing with the thumb on the branch between the alternator and fan pulleys for the alternator drive belt and when pressing with...
Engine mount elements
Engine mount: A - up to 1979 model year; B - since 1979 model year. 1 — right suspension bracket; 2 — left suspension bracket; 3 - support; 4 — spacer; 5 -...
Engine mount: A - up to 1979 model year; B - since 1979 model year. 1 — right suspension bracket; 2 — left suspension bracket; 3 - support; 4 — spacer; 5 -...
Exhaust gas system
Exhaust system: 1 - exhaust manifold; 2 - protective cover; 3, 5 - gaskets; 4 - exhaust pipe; 6 — bracket for mounting the inlet pipe; 7 - additional muffler;...
Exhaust system: 1 - exhaust manifold; 2 - protective cover; 3, 5 - gaskets; 4 - exhaust pipe; 6 — bracket for mounting the inlet pipe; 7 - additional muffler;...
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