air pump BMW 645Ci COUPE 2004 E63 N62B44 Engine Workshop Manual
[x] Cancel search | Manufacturer: BMW, Model Year: 2004, Model line: 645CI COUPE, Model: BMW 645CI COUPE 2004 E63Pages: 55, PDF Size: 1.05 MB
Page 1 of 55

Downloaded from www.Manualslib.com manuals search engine Table of Contents
SubjectPage
N62B44 Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Objectives of the Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Purpose of the System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Engine Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Components
Fresh Air System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
- Air Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
- Throttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
- Intake Manifold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
- Crankcase Venting System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
- Exhaust Manifold with Catalytic Converter . . . . . . . . . . . . . . . . . . . . . . . 13
- Silencers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
- Secondary Air System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Ancillary Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
- Belt Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
- Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
- Air Conditioning Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
- Starter Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
- Power Steering Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Cylinder Heads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
- Engine Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
- Valve Gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
- Valvetronic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
- Bi-VANOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
- Vacuum Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
- Chain Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Page 7 of 55

Downloaded from www.Manualslib.com manuals search engine 5
N62 Engine
Engine Views
1
2
3
45
6
7
42-02-03 N62B44 Engine (Front View)
1. Starter Motor
2. Valvetronic Motor
3. Evaporative Emission Valve
4. VANOS Solenoid Valve
5. Thermostat Housing
6. Throttle Unit
7. Vacuum Pump
N62B44 Engine (Rear View)
1. Camshaft Position Sensor
Cylinder Bank 5-8
2. Valvetronic Eccentric Shaft
Position Sensor, Cylinder
Bank 5-8
3. Valvetronic Eccentric Shaft
Position Sensor, Cylinder
Bank 1-4
4. Camshaft Position Sensor
Cylinder Bank 1-4
5. Secondary Air Non-return Valves
6. Servomotor for Variable Intake
Manifold
42-02-04
Page 8 of 55

Downloaded from www.Manualslib.com manuals search engine Fresh Air System
Air Routing
The intake air passes through the air intake duct to the air cleaner, through the throttle sec-
tion into the variable intake manifold and on to the two cylinder head intake ducts.
Increases in engine output and engine torque, as well as optimization of the engine torque
curve, are largely dependent on an optimum engine volumetric efficiency over the entire
engine speed range.
Long and short intake paths contribute to good volumetric efficiency in the lower and upper
speed ranges. Long air intake paths ensure optimum volumetric efficiency in the lower to
middle speed ranges. This optimizes the torque curve and increases the torque.
In order to optimize the power increase in the upper speed range, the engine requires short
air intake paths for better cylinder filling. The air intake system has been completely rede-
velopd in order to eliminate this inconsistency in terms of air intake path length.
The air intake system consists of the following components:
6
N62 Engine
42-02-05 Air Intake System
1. Air Intake Duct
2. Air Cleaner Housing with Intake
Air Silencer
3. Intake Pipe with HFM (Hot-Film
Air-Mass Flow Sensor)
4. Secondary Air Valves
5. Secondary Air Pump
Page 16 of 55

Downloaded from www.Manualslib.com manuals search engine Silencers
• A 1.8 liter capacity front silencer has been fitted for each cylinder bank.
• A single 5.8 liter center silencer is fitted downstream of the two front silencers.
• The resonator type rear silencers have capacities of 12.6 and 16.6 liters.
Exhaust Gas Flap
The 12.6 liter rear silencer is fitted with an exhaust gas flap to keep noise to a minimum at
engine idle speed and low rpm. The exhaust gas flap is opened allowing additional flow
when:
• The a transmission gear is engaged a an
nd
d
• The engine speed is above 1,500 rpm
A vacuum-controlled diaphragm (actuator mounted on the silencer) opens and closes the
exhaust gas flap. The exhaust gas flap is closed with vacuum, and is sprung open by the
actuator (when vacuum is not present). The procedure is carried out using a solenoid valve
which is electrically controlled by the ECM.
Secondary Air System
Blowing additional air (secondary air) into the cylinder head exhaust ducts during the warm-
up phase results in a thermal secondary combustion which results in a reduction of the
non-combusted hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas. The
energy generated during this process heats up the catalytic converter faster during the
warm-up phase, and increases it’s conversion rate.
14
N62 Engine
43-02-05
Secondary Air System
1. Air Intake Duct
2. Air Cleaner housing with Intake Air Silencer
3. Intake Pipe with HFM (Hot-Film Air-Mass
Sensor)
4. Non-return Valves
5. Secondary Air Pump
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Downloaded from www.Manualslib.com manuals search engine Secondary Air Pump (SLP)
The electrically-operated secondary air pump is mounted to the vehicle body. The pump
draws out filtered fresh air from the air cleaner housing during the warm-up phase and sup-
plies it to the two secondary air Non-return Valves.
Once the engine has been started, the secondary air pump is supplied with voltage by the
ECM via the secondary air pump relay. It remains switched on until the engine has taken in
a certain amount of air.
The O ON
N
period may be a maximum of 90 seconds and it depends on the following engine
operating conditions:
• Coolant temperature (from -10 ºC to approximately 60 ºC)
• Air temperature (NTC sensor in HFM)
• Engine speed
One non-return valve is mounted on each cylinder head (see also Engine Views).
The non-return valves are opened by the pressure generated from the secondary air pump.
The secondary air is led through a pipe to the secondary air ducts (integral in the cylinder
heads) for distribution into the exhaust ports.
The non-return valves are sprung closed when the secondary air pump is deactivated. This
prevents exhaust vapors, pressure and condensation from flowing back into the secondary
air pump.
15
N62 Engine
43-02-14
View From Rear of The Cylinder Head
1. Cylinder Head Lead
2. Non-return Valve (SLV)
3. Secondary Air Pump Connection
Page 18 of 55

Downloaded from www.Manualslib.com manuals search engine Ancillary Components and Drive Belts
Drive Belts
The belt drive has two components and is subdivided into the main and A/C drives. Both
belts are driven by the crankshaft pulley.
A 4 rib belt is used to drive the air conditioning compressor and a 6 rib belt is used for the
main drive. Each drive belt has a maintenance free tensioning unit with tensioning pulley
and torsioner.
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The tensioning pulley is pushed back using a
Torx tool in the recess provided (1) and fixed in
this position by inserting a locking pin as shown
(2).
16
N62 Engine
42-02-15 Ancillary Components and
Drive Belts
1. Air Conditioning Compressor
2. 4 Rib A/C Drive Belt
3. Crankshaft Pulley
4. Water Pump
5. Tensioning Unit Main Drive Belt
6. Alternator
7. Deflection Pulley
8. Power Steering Pump
9. 6 Rib Drive Belt
10. Tensioner Unit A/C Drive Belt
42-02-16
Page 21 of 55

Downloaded from www.Manualslib.com manuals search engine N No
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The alternator regulator voltage is influenced by the ECM - BSD interface. The bat-
tery charge voltage can therefore be up to 15.5 V, depending on the battery temperature.
If a battery charge voltage of up to 15.5 V is measured, the regulator is not faulty. A high
charge voltage indicates a low battery temperature.
Air Conditioning Compressor
The “clutch free” A/C compressor is manufac-
tured by Denso. It functions continuously with
the engine running. The compressor is a 7-
cylinder swash plate type. The displacement
can be reduced to less than 3% when air con-
ditioning is not requested (no refrigerant is sup-
plied to the refrigerant circuit).
There is an internal compressor refrigerant cir-
cuit to maintain lubrication. The IHKA electron-
ics regulate the compressor output via an
external control valve (1).
Starter Motor
The starter motor is located on the right-hand
side of the engine below the exhaust manifold,
and is a compact planetary drive starter with a
1.8 kW output.
1. Starter motor with heat protective cover.
Power Steering Pump
The power steering pump is a tandem radial piston pump on vehicles equipped with
Dynamic Drive. A single vane pump is installed on vehicles without the Dynamic Drive.
Further information about the power steering pump can be found in the Chassis Dynamics
section.
19
N62 Engine
42-02-19
42-02-03
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N62 Engine
The chart below shows the VANOS unit camshaft adjustment possibilities. The valve lift
adjustment has also been incorporated.
The special feature of Valvetronic is that the air mass drawn in the cylinders can be easily
determined by the valve lift and closing time. The air mass can then be limited, thus the
term “load control”.
With the help of VANOS, the valve closing point can be easily selected within a defined
range. With valve lift control, the opening duration and cross section of the valve opening
can also be easily selected within a defined range.
Vacuum pump
The N62 engine requires a vacuum pump for the vacuum
assisted brake booster. With the throttle valve open while the
car is being driven, additional vacuum is needed.
The N62 vacuum pump has a second vacuum connection
(small hose) for the exhaust flap adjustment. The vacuum
pump is driven by cylinders 1-4 exhaust camshaft via the
VANOS unit. The pump is lubricated through an oil gallery
from the cylinder head.
42-02-03
Chart Exhaust & Intake Valve
1. Exhaust Valve Open
2. Exhaust Valve Closed
3. Intake Valve Open
4. Intake Valve Closed
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N62 Engine
Coolant Circuit
The coolant flow has been optimized allowing the engine to warm up as quickly as possi-
ble after a cold start as well as even and sufficient engine cooling while the engine is run-
ning. The cylinder heads are supplied with coolant in a cross-flow pattern. This ensures
more even temperature distribution to all cylinders. The cooling system ventilation has been
improved and is enhanced by using ventilation ports in the cylinder heads and in the radi-
ator. The air in the cooling system accumulates in the expansion tank. When a pressure of
2 bar is reached in the expansion tank, the air is bled out by the pressure relief valve in the
reservoir cap.
N No
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The ventilation ports in the front of the cylinder heads provide quicker “self bleeding”
during a routine coolant exchange. The complex cooling system and the small ventilation
ports require that time should be allowed after the cooling system has been filled for the air
to escape.
Coolant flow in the Engine Block
The coolant flows from the water pump through the feed pipe (1) in the engine's V and to
the rear of the engine block. This area has a cast aluminum cover (see following illustration).
From the rear of the engine, the coolant flows to the external cylinder walls and from there
into the cylinder heads.
The coolant then flows from the cylinder heads into the engine block V and through the
return connection (3) to the thermostat housing. When the coolant is cold it flows from the
thermostat (closed) directly into the water pump and back to the engine (recirculating for
faster warm up).
When the engine reaches operating tempera-
ture (85 ºC-110 ºC), the thermostat opens the
entire cooling circuit to include the radiator.
42-02-57
Engine Block Coolant Flow
1. Coolant from the water pump through the feed pipe
to the rear of the engine.
2. Coolant from the cylinder walls to the thermostat
housing.
3. Return connection to water pump/thermostat.
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N62 Engine
Cooling Radiator
The radiator is made from aluminum and is divided into a high-temperature section and a
low-temperature section by a partition wall (see coolant circuit diagram). The coolant first
flows into the high-temperature section and then back to the engine, cooled.
Some of the coolant flows through an opening in the radiator partition wall to the low-tem-
perature section where it is cooled further. The coolant then flows from the low-tempera-
ture section (when the ÖWT thermostat is open) into the oil/coolant heat exchanger.
Coolant Expansion Tank
The expansion tank is mounted on the right hand wheel housing (engine compartment).
N No
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The expansion tank should never be filled above the Max marking. Excess coolant is
expelled by the pressure relief valve in the cap as it heats up. Avoid overfilling the expan-
sion tank because the cooling circuit design ensures very good “self bleeding”.
Cooling Components
1. Cooling Radiator 4. Engine oil/air heat exchanger connection
2. Expansion Tank (hot countries only)
3. Water Pump 5. Transmission oil/coolant heat exchanger