General information about the engine On BMW 5 Series models «518», «520», «520i» a four-cylinder engine was installed, on models «520» from model year 1978, «520i», «525», «525i», «528», «52Bi»,...
Cylinder head specifications The head is cast from aluminum alloy, it has combustion chambers with transverse gas movement (models «518», «520», «520i») or trispherical combustion chambers...
Cylinder Block Specifications The cylinder block is cast from special gray cast iron and is one piece with the cylinders. Grinding of the plane of the cylinder block connector with the head...
Valve Timing Specifications The engine uses a valve timing mechanism with an overhead camshaft, which is driven by a double-row roller chain or toothed belt (BMW «520» from model year...
Removing the cylinder head Note. This and the following sections provide recommendations for the repair and maintenance of BMW vehicles «518», «520» And «520»» with 4-cylinder engine,...
Disassembly of the cylinder head Remove the ignition distributor and its mounting bracket. Place the cylinder head on stand 6025/1 (models «518», «520») or on stand 7003/1 (models «525»,...
Checking the technical condition of the cylinder head Before checking, flush all parts with trichlorethylene, clean the mating surface of the cylinder head with a scraper, clean the combustion chambers and exhaust...
Cylinder head repair Replacing valve guides If one of the valve guides is heavily worn (see wear limits in subsection « Detailed Specifications ») replace it. With a cold engine,...
Cylinder head assembly Thoroughly clean and check the condition of the parts. Reassembly of the cylinder head is carried out in the reverse order of disassembly, taking into account...
Intake manifold BMW Engine Intake Manifold «520»: 6 - adjusting screw for air intake; 7 - temperature sensor of the carburetor starting device; 9 - vacuum selection valve....
Installing the cylinder head After cleaning the mating surface of the cylinder block, check the protrusion of the dowel pins above its plane, which should not exceed 5 mm. Make sure the...
Valve clearance adjustment The clearances in the valve drive mechanism are adjusted by slightly opening the valves by turning the adjusting eccentric of the rocker arm, after loosening...
Removal and installation of the engine Withdrawal Disconnect the wires from the battery terminals, drain the liquid from the cooling system by unscrewing the drain plugs on the radiator and cylinder...
Removal and installation of the power unit Removal and installation of the power unit are carried out similarly to the removal and installation of the engine. At the same time, to move the engine...
Engine disassembly Install the washed and cleaned engine on the turntable 6000 for disassembly using the mounting plate 6001 (models «518», «520») or plates 7001 (models «525»,...
Details of the crank mechanism Details of the crank mechanism: A - engine «5201» with Kugetfischer fuel injection system; A1 - engine models «518», «520»; A2 - engine models «525», «528». 1...
Installing the crankshaft Make sure that the crankshaft journals and main bearing shells are the same size group. Color indexes (red or blue) on the main bearing shells must be...
Replacing the flywheel gear rim Check the condition of the flywheel gear rim and in case of significant tooth wear, replace the gear rim. Drill a hole approximately 8mm deep in the rim just...
Flywheel grinding The plane of contact of the driven disk on the flywheel must be smooth, without scratches and scuffs. Risks and scuffs are removed by grinding. After grinding...
Checking the axial clearance of the crankshaft Install the crankshaft rear oil seal holder with a new gasket. Install the flywheel on the crankshaft. Block the flywheel with retainer 7007, install new...
Installing the camshaft drive Install the guide and chain tensioner shoe (see picture «Camshaft Drive Diagram») and make sure the shoe turns freely on its axis. Slide the pulley onto the...
Details of the gas distribution mechanism Details of the timing mechanism of a 4-cylinder engine: 1 - camshaft sprocket; 2 - axes of the rocker arms of the intake and exhaust valves; 7 - rocker; 9 — an...