The valvetrain on the N52 introduced in 2006, used 5 mm valve stems on both
the intake and exhaust. To
increase durability, the exhaust valve stems were increased to 6 mm from 6/06
production.
All of the new NG6 engine have adopted the 6 mm valve stem for the exhaust, the
intake stem remains at
1. General information on handling rubber seal profiles:
If seals reveal partly detached protective film on delivery, they must
not be bonded.
Store seals at 15 ºC to 25 ºC.
If, during the handling, the protective film has come off before
bonding, it can still be bonded.
Bonding at room a