X Series E83 X3 2.5Si (N52K) OFFRD
The N52 has a volume-flow-regulated oil pump. This pump only delivers as much oil as each operating range of
the engine requires. A conventional oil pump would have to be approximately three times the size of that in the
N52 engine. This oil pump would also require more driving power accordingly.
No superfluous oil is supplied for ranges with a smaller load. The fuel consumption of the engine is reduced and
wear to the oil is slowed down. A pendulum slide cell pump is used. The pump shaft is located off-centre in the
housing during pump activation. The impeller shifts radially during rotation. This means that the chambers on the
impeller form different volumes. The oil is taken into the enlarging volume. The oil is pumped into the oil ducts at
the reducing volume.
Oil level check, engine oil quality check and engine oil temperature check
The oil level is measured by the oil condition sensor and shown in the Central Information Display (CID). This
protects the engine from excessively low oil level and the associated engine damage. Excessive oil filling of the
engine, which can lead to leaks, is displayed as a check control message.
The oil condition sensor also registers the engine oil quality. This means that the system is able to compute
exactly when it is necessary to change the engine oil. Condition Based Service (CBS) allows the engine oil to be
changed in line with needs.
The engine oil temperature is also detected or calculated by the oil condition sensor. The signal from the oil
condition sensor is evaluated in the DME. The evaluated signal is routed via the PT-CAN and K-CAN bus to the
instrument cluster and to the CID.
Valvetronic
The Valvetronic consists of fully variable control of the valve lift combined with the variable camshaft control unit
(VANOS).
The valve lift is only regulated on the inlet side, but the camshaft is also adjusted on the exhaust side.
Valvetronic is controlled by:
-
a variable valve lift of the inlet valve
-
a variable opening duration of the inlet valve
-
a variable camshaft control of the inlet and exhaust camshaft
(double VANOS)
The system is optimised by adapting the valve gear, changing the actuator motor and varying the camshaft
timing control. Major innovations are:
-
On the intermediate lever, the plain bearing to the eccentric shaft has been replaced by a roller bearing.
This reduces the friction in the valve gear.
-
The guide of the intermediate lever is more precise. Only one spring is required to guide and retain the
intermediate lever.
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The moved mass of the valve gear has been reduced by 13%.
-
The range of motion of the inlet valves has been improved. The maximum lift has risen to 9.9 mm, but
above all the minimum lift has been further reduced to 0.18 mm.
Heat management
The possibilities of conventional cooling systems are used for the cooling system with electrical coolant pump.
The following components are influenced by the heat management:
•
Electrical coolant pump
•
Mapped thermostat
•
Digital engine electronics (DME)
The cooling output of the system is adapted by means of a freely variable volumetric flow of the coolant.
The heat management determines the current cooling requirement and regulates the cooling system
SBT N52 engine E60, E61, E63, E64, E65, E66, E70, E81, E82, E83, E85, E86, E87, E90,
BMW AG - TIS
12.02.2013 09:50
Issue status (12/2007) Valid only until next DVD is issued
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