BMW N62B44, Руководство пользователя

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Principle of Operation
T Th he e V Va allv ve ettrro on niic c s sy ys stte em m iis s a a c co om mb biin na attiio on n o off V VA AN NO OS S a an nd d v va allv ve e lliifftt a ad djju us sttm me en ntt.. This combi-
nation of abilities allows the ECM to control when the intake valves are opened and closed,
and also the opening lift. The intake air flow is set by adjusting the valve lift while the throt-
tle valve is fully opened. This improves cylinder filling still further and reduces fuel con-
sumption.
Each cylinder head in the N62 engine has a Valvetronic assembly. This Valvetronic assem-
bly consists of a bridge support with eccentric shaft, intermediate levers with retaining
springs, drag lever and the intake camshaft.
In addition, the following components belong to
the Valvetronic system:
• A Valvetronic motor for each cylinder head
• A Valvetronic control module
• A Valvetronic sensor for each cylinder head
The intake valve lift can be adjusted to anywhere between 0.3 mm and 9.85 mm.
The cylinder heads are precision manufactured together to ensure precise flow rate and
uniform distribution. The valve gear components on the intake side are precisely matched
together to the tightest limits.
The bridge support, lower eccentric shaft and inlet camshaft bearings are matched togeth-
er in the cylinder head once it is assembled. If the bridge support or the lower bearings are
damaged, the entire assembly must be replaced.
N No otte es s::
25
N62 Engines
42-02-30