BMW 5251 Service Manual page 194

116-18
Cylinder Head and Valvetrain
4
Install camshaft carriers with hydraulic lifters into cylinder
head. Note marks on carriers: (E) for intake side and ( A ) for
exhaust side.
4
Center camshaft carrier on pins (arrows) at bearing posi-
tions
2
and 7.
4
Install camshafts with number 1 cylinder camshaft lobes fac-
ing each other (arrows).
CAUTION-
A minimum waiting time is required for the hydraulic lifters to
'bleed down" after installing the camshafts into the cylinder
head, before bringing the pistons to TDC. When the cam-
shafts are removed, the hydraulic lifers can expand. This ex-
pansion can cause increased valve lift when the camshafts
are bolted down, possibly resulting in piston interference.
Camshaft Installation waiting times
68"
F
(20" C)
or above
4
minutes
50-68' F (1 0-20°C) 11
minutes
32-50" F (0-1 0" C)
30
minutes