5.0. Valve mechanism. Cars with AFB, AKE, AKN, AYM, BFC engines:
1 - Front camshaft bearing cover
2 - deaf (cap) camshaft bearing front cover fastening nut. Tightening torque - 15 Nm
3 - camshaft bearing cover mounting bolt. Tightening torque - 10 Nm
4 - deaf (cap) camshaft bearing cap fastening nut. Tightening torque - 15 Nm
5 - nut. Tightening torque -10 Nm
6 - camshaft bearing cover mounting bolt. Tightening torque -10 Nm
7 - camshaft bearing cap
8 - intake camshaft
9 - exhaust camshaft
10 - hydraulic pusher
11 - brake booster pump mounting bolt. Tightening torque - 10 Nm
12 - brake booster pump
13 - thrust half rings of the camshaft bearing
14 - cylinder head
15 - exhaust valve
16 - inlet valve
17 - camshaft oil seal
18 - camshaft gear
19 - central bolt for fastening the camshaft gear. Tightening torque - 75 Nm
20 - oil seal
21 - valve spring
22 - valve spring plate
23 - valve cracker
24 - hydraulic pusher
25 - valve rocker arm guide bushing
26 - valve rocker
5.0a. Valve mechanism. Cars with engine:
1 - valve
2 - cylinder head
3 - oil supply valve
4 - oil seal
5 - valve spring
6 - valve spring plate
7 - valve spring crackers
8 - camshaft oil seal
9 - Front camshaft bearing cover
10 - sealing gasket
11 - deaf (cap) camshaft bearing front cover fastening nut. Tightening torque - 15 Nm
12 - camshaft bearing cap
13 - camshaft bearing cover mounting bolt. Tightening torque - 10 Nm
14 - camshaft bearing cover fastening nut. Tightening torque - 10 Nm
15 - sealing gasket
16 - deaf (cap) camshaft bearing front cover fastening nut. Tightening torque - 15 Nm
17 - rear cover of the camshaft bearing
18 - intake camshaft
19 - exhaust camshaft
20 - roller type rocker arm
21 - hydraulic pusher
22 - thrust half rings of the camshaft bearing
23 - threaded pin of the camshaft bearing cap
5.0b Valve:
a - valve plate diameter: inlet valve - 27.00-27.20 mm; exhaust valve - 24.00-24.20 mm
b - valve stem diameter - 5.958-5.972 mm
c - valve stem length - 100.35-100.65 mm
α - valve plate chamfer angle - 45°
The original source of the article can be found on the website AudiManual