Removal
Caution: Operating procedures and instructions applicable to all diesel engines are given in the chapter dedicated to the 525tds engine (m51S engine). The differences described below are specific to the 520d engine only. The tightening method for the cylinder head bolts also applies to the M47 engine.
Remove the vacuum pump, see the relevant chapter.
Remove the cylinder head cover.
Fix the engine crankshaft in the TDC position for cylinder 1 using the BMW 11 2 300 device or another suitable pin. To do this, insert the pin through the hole in the cylinder block under the starter into the hole in the flywheel.
Fix the chain tensioner in the compressed position. To do this, unscrew the plug with the internal hexagon from the end of the cylinder block "arrow" and insert the pin BMW 113 340 or another similar one into the hole.
Loosen the upper chain guide fastening.
Loosen the fastening of both sprockets to the camshafts. Hold the camshafts by the hexagons on them. To fix the intake camshaft, BMW service stations use the BMW 11 6 320 device.
Remove the camshaft bearing caps and place them in accordance with the existing markings. Remove the camshafts.
Remove the valve lifters from the cylinder head and place them in the correct order.
Tightening torques during installation:
- Chain tensioner fixing hole plug: 30 Nm (replace the sealing gasket);
- fastening of sprockets to camshafts: 20 Nm and turn further by 35° in the tightening direction.