BMW 5251 Service Manual page 309

1
Camshaft Timing Chain
4
Secure right side timing chain and guide rails together with a
plastic wire ties (arrow).
4
Remove lower timing chain cover bolts (arrows) and cover.
-
Remove wire ties supporting guide rails.
-
Q
Remove sprocket from intake camshafts and remove timing
chain.
If necessary, remove tensioning rail (A), reversing rail (B),
and guide rail (C) to remove timing chain.