Oil outside of bucket tappets and reinstall on original valves.
Measure thickness of shims with micrometer and note down dimension.
Place lower part of camshaft carrier (1) on cylinder head.
Fit camshafts with cam lobes facing upwards, press down by hand and measure valve clearance with feeler gauge.
Note: The decompressor in the exhaust camshaft must not press against the bucket tappet, or else the valve clearance will be incorrect.
Note down dimensions.
Determine the difference between the nominal and actual values.
Check thickness of shims with micrometer and replace as appropriate.
Valve clearances:
- Inlet valve: 0.05...0.10 mm (0.002...0.004 in)
- Exhaust valve: 0.25...0.30 mm (0.010...0.012 in)
Insert chain guide rail (3) in chain cavity.
Cauton! Marks on the timing-chain sprockets (arrow) must be parallel with the cylinder head, the bores in the timing-chain sprockets must be at the top (TDC position).
Oil the camshaft journals.
Install the exhaust camshaft first, then the inlet camshaft.
Install the upper part of the camshaft carrier (2) and tighten.
Clean the threads of the chain guide fasteners (4), coat with Loctite 243 and install the fasteners.
Check valve clearances.
Install chain tensioner and tighten threaded fastener with sealing ring.
Remove all traces of the cylinder head cover gasket and clean the sealing face with degreasing agent. Also clean the groove and the seating faces for the gasket.
Install valve cover with gasket.
Connect the oil lines to the engine block.
Note: Install the oil return line with the tab at the bottom and the oil feed line with the tab at the top.
Connect the oil lines to the cylinder head.
Take out locating pin, BMW No. 11 6 570, and insert screw plug with sealing ring.
Install the spark plug.
Fit the filter element onto the oil-filter cover.
Coat the O-ring of the filter element lightly with oil.
Check the O-ring of the oil-filter cover for damage and replace if necessary.
Install the oil-filter cover complete with filter element.
Install starter motor.
Tightening torque:
- Camshaft bearing cap: 10 Nm
- Chain guide to bearing cap (clean threads + Loctite 243): 10 Nm
- Timing-chain tensioner to cylinder head: 40 Nm
- Cylinder head cover to cylinder head: 10 Nm
- Threaded plug in left side of engine block: 25 Nm
- Oil line to engine block: 35 Nm
- Oil line to cylinder head: 8 Nm
- Spark plug in cylinder head: 20 Nm
- Starter motor to clutch housing cover: 10 Nm
- Oil filter cover: 10 Nm