BMW M52B25TU

BMW M52B25TUThe BMW M52B25TU is a 2.5 L (2,494 cc, 152.2 cu·in) straight-six, natural aspirated four-stroke gasoline engine, manufactured by BMW since 1998 to 2000 on Munich Plant (Munich, Germany). The M52B25TU engine is a technical update of the M52B25 engine. The main “technical update” for M52TU was the addition of double VANOS.

The cylinder bore is 84.0 mm (3.31 in) and the piston stroke is 75.0 mm (2.95 in). The compression ratio rating is 10.5: 1.

This engine produced 170 PS (125 kW; 167.6 HP) at 5,500 rpm of horsepower and 245 N·m (25 kg·m, 180.6 ft·lb) at 3,500 rpm of torque.

The BMW M52B25TU features:

  • Cast-aluminum alloy cylinder block with cast-iron cylinder liners
  • Aluminum cylinder head
  • DOHC design with 4 valves per cylinder (24 valves in total)
  • Distributorless ignition system with individual ignition coils for each cylinder
  • Distributorless ignition system with individual ignition coils for each cylinder
  • Electronic fuel injection (EFI)
  • Siemens MS 42.0 DME (Digital Motor Electronics) system
  • Double VANOS (Variable Valve Timing System from BMW)
  • Motor Driven Throttle Valve
  • Dual length intake manifold (called “DISA” by BMW)

General information

Engine Specifications
Engine model M52B25TU
Engine type Straight-six, 4-stroke, DOHC, inline
Displacement 2.5 L, (2,494 cm3, 152.2 cu·in)
Max. horsepower 170 PS (125 kW; 167.6 HP) at 5,500 rpm
Max. torque 245 N·m (25 kg·m, 180.6 ft·lb) at 3,500 rpm
Cooling system Liquid-cooled
Lubricating system Pressure feed
Ignition system Distributorless ignition system with individual ignition coils for each cylinder
Fuel system Electronic fuel injection (EFI)
Starting system Starter 12V
Firing order: 1-5-3-6-2-4
Dimensions (L x W X H)
Dry weight 175 kg(385 lbs)

Cylinder Block and Head

Cylinder block
Cylinder block alloy: Aluminium
Compression ratio: 10.5: 1
Cylinder bore: 84.0 mm (3.31 in)
Piston stroke: 75.0 mm (2.95 in)
Cylinder internal diameter (standard): 84.000-84.010 mm (3.3071-3.3075 in)
Piston skirt outer diameter (standard): 83.980-83.989 mm (3.3063-3.3066 in)
Number of piston rings (compression / oil): 2/1
Piston pin diameter: 22.000 mm (0.8661 in)
Side clearance (Top): 0.020-0.060 mm (0.0008-0.0024 in)
Side clearance (Second): 0.030-0.065 mm (0.0012-0.0026 in)
Side clearance (Oil): 0.020-0.060 mm (0.0008-0.0024 in)
Ring end gap (Top): 0.100-0.300 mm (0.0039-0.0118 in)
Ring end gap (Second): 0.200-0.400 mm (0.0079-0.0157 in)
Ring end gap (Oil): 0.250-0.500 mm (0.0098-0.0197 in)
Number of main bearings: 7
Crankshaft main journal diameter: 60.000 mm (2.3622 in)
Crankpin journal diameter: 45.000 mm (1.7717 in)
Crankshaft center distance: 37.5 mm (1.475 in)
Cylinder head
Cylinder head alloy: Aluminium
Valve arrangement: DOHC, chain driven
Valves: 4,(24 valves in total)
Head height: 140.0 mm (5.5118 in)
Valve head diameter (INTAKE): 33.0 mm (1.2992 in)
Valve head diameter (EXHAUST): 30.5 mm (1.2008 in)
Valve steam diameter (INTAKE): 6.0 mm (0.2362 in)
Valve steam diameter (EXHAUST): 6.0 mm (0.2362 in)

Service Data

Compression pressure
Minimum: 10.0 kg/cm2 (9.9 bar, 145 psi) / 350 rpm
Compression differential limit between cylinders: 1.0 kg/cm2 (1.0 bar, 15 psi) / 350 rpm
Oil system
Lubrication system: Pressure feed
Oil type: BMW High Performance Synthetic (API SH)
Recommended oil: SAE 5W-30
Oil capacity: 6.5 L (6.87 US. qt, 5.72 Imp. qt.)
Oil change interval, km (miles) 5,000-10,000 (3,000-6,000)
Fuel system
Type: Electronic fuel injection (EFI)
Ignition system
Type: Distributorless ignition system with individual ignition coils for each cylinder
Spark plug: Bosch: FGR7DQP, NGK: BKR6EQUP
Spark plug torque: 25 N·m (2.5 kg·m, 18.4 ft·lb)

Applications

Model Years Produced
BMW 323i, 323Ci (E46) 1998-2000
BMW 525i (E34) 1998-2000
BMW Z3 2.3i (E36/7 ) 1998-2000
BMW 323ti Compact (E36) – with single VANOS 1999-2000

Be the first to comment

Leave a Reply

Your email address will not be published.


*