BMW 3 Series Repair Manual: 325i, 325xi, 328i, 328xi, 330i, 330xi, 335i, 335xi, 2006-2010

• 325i, 330i, N52 engine (rear-wheel drive)
• 328i, N52KP, N51 engine (rear-wheel drive)
• 325xi, 330xi N52 engine (all-wheel drive or xDrive)
• 328xi N52KP, N51 engine (all-wheel drive or xDrive)

• 335i N54 engine (rear-wheel drive)
• 335xi N54 engine (all-wheel drive or xDrive)

• Getrag GS6-17BG manual
• ZF GS6-37BZ(X) manual
• ZF GS6-53DZ(X) manual
• GM GA6L45R automatic
• ZF GA6HP19Z automatic

CRANKCASE BREATHER VALVE (NON-TURBO)

Non-turbo engine crankcase is ventilated by either a breather valve under the intake manifold or a breathe valve integrated in the cylinder head cover. Engines with a metal cylinder head cover utilize an external breather valve; engines with a plastic valve cover utilize an internal breather valve.

See illustration. The crankcase ventilation system has an electrically heated crankcase breather valve. The pressure control valve and cyclonic oil separator are combines into one unit. The assembly is located under the intake manifold (see arrow).

The pressure control valve varies the vacuum applied to the crankcase breather depending on engine load. The valve is balanced between spring pressure and the amount of manifold vacuum.

At idle when the intake manifold vacuum is high, vacuum reduces the valve opening, allowing a small amount of crankcase vapors to be drawn into the intake manifold.

At part to full load conditions when intake manifold vacuum is lower, the spring opens the valve and additional crankcase vapors are drawn into the intake manifold.

CLUTCH COMPONENTS | INSPECTING

• Inspect clutch disc for wear, cracks, loose rivets, contamination or excessive runout (warping). Replace if necessary.



• Measure depth of clutch lining at lining rivets. If shallowest rivet depth is less than 1 mm (0.04 in), replace clutch disk.



• Inspect flywheel for scoring, hot spots, cracks or loose or worn guide pins. Replace flywheel if any faults are found. See Flywheel, removing and installing in this repair group.


CAUTION! If flywheel is removed from engine, install using new bolts.


• Check to make sure transmission pilot bearing rotates smoothly without play. Replace if faulty. See Transmission pilot bearing, replacing in this repair group.



• Inspect and clean release bearing module.



• See illustration. Check release bearing ball stud and spring retainer. Replace if damaged or worn.



• Clean release bearing guide sleeve.

• General Data and Maintenance
• Engine
• Engine Removal and Installation
• Cylinder Head Removal and Installation
• Lubrication System
• Ignition System
• Fuel Injection
• Radiator and Cooling System
• Exhaust System
• Transmission
• Manual Transmission
• Automatic Transmission
• Suspension, Steering and Brakes
• Steering and Wheel Alignment
• Rear Suspension
• Brakes
• Body
• Body Equipment
• Exterior Trim, Bumpers
• Central Locking and Anti-Theft
• Convertible Top
• Electrical System
• Electrical Component Locations
• Instruments
• Heating and Air Conditioning
• Equipment and Accessories
• Airbag System (SRS)
• Electrical Wiring Diagrams