BMW N52

BMW N52 engine
Overview
Manufacturer	BMW, Bayerische Motoren Werke AG
Production	2004–2011
Combustion chamber
Configuration	Straight-6
Chronology
Predecessor	BMW M54
Successor	BMW N53 (except North America, Australia and Malaysia), BMW N20 (North America, Australia and Malaysia)

The BMW N52 is a straight-6 DOHC piston engine which replaced the M54 and was produced from 2004 to 2011. Compared with its M54 predecessor, the N52 features variable valve lift (called Valvetronic by BMW) and also Dual VANOS, a continuous variable valve timing control for both inlet and exhaust camshafts. The N52 crankcase is made entirely of magnesium and aluminum.^[1] The N52 debuted in the 2004 BMW E63 630Ci.

All BMW nameplates (3 series, 5 series, X3, Z4, etc.) have been offered with an N52 engine. The N52 was replaced with the N53, however since the N53 was not sold in North America, Australia or Malaysia,^[2] these markets continued to use the N52 until the introduction of the N53's successor, the N20 turbocharged 4-cylinder engine.^[3]

Design

The N52 engine block is cast with magnesium and aluminum for the crankcase. Magnesium is used to save weight, however magnesium is subject to a greater risk of corrosion from water. Moreover, magnesium may tend to creep under load at high temperatures. Thus, magnesium in its pure form or as a conventional alloy is not suited for permanently conveying high loads and forces of the kind typically encountered in central components of the engine. Therefore, BMW combined the N52 block to use magnesium alloy for the crankcase shell, with an aluminum “inner block” to complement the magnesium disadvantages.^[4][5]

For the cylinder liners the N52 Engine uses Alusil to coat the aluminum cylinder sleeves. Alusil is an aluminium alloy commonly used to make linerless aluminium alloy engine blocks. Alusil, when etched, will expose a very hard silicon precipitate. BMW switched from Nikasil-coated cylinder walls to Alusil in 1996 to eliminate the corrosion problems caused through the use of petrol or gasoline containing sulphur.^[6]

Hydraulic Valve Adjuster problems

The ticking noise of Hydraulic Valve Adjuster is a known problem with the N52 (3.0L) engine fitted with manufacturing date prior to November 2008. An occasional ticking or rattling noise from the HVA elements may occur during cold engine starts or frequent short-distance driving, recently known after the engines reach 50.000 miles. In these situations, the HVA elements may not yet have been supplied with sufficient amounts of air-free oil. This condition will not cause any damage to the engine, and usually remedies itself with a longer driving distance or operating times at full operating temperature. BMW dealers' first response is to perform HVA bleeding procedure, however this procedures seems not to resolve the matters. The second attempt to solve this problem is a replacement with improved HVA parts, however this procedures also does not fully address the problem. Finally, a newly designed cylinder head replacement solves the ticking noise problem for vehicles under warranty. Vehicles produced after November 31, 2008 have already been fitted with improved cylinder head that resolves this HVA problems.^[7]

Models

N52B25

N52B25 from a BMW 325 Coupé

The N52B25 comes in three versions, all displacing 2.5 L (2497 cc/152 in³). The least powerful produces 130 kW (174 hp) at 5800 rpm and 230 N·m (170 lb·ft) at 3500-5000 rpm.^[8] There is also a version producing 150 kW (200 hp) at 6400 rpm and 250 N·m (180 lb·ft) at 2750 rpm.^[9] The most powerful N52B25 produces 160 kW (218 hp) at 6500 rpm and 250 N·m (184 lb·ft) at 2750–4250 rpm.^[10]

130 kW Applications:

• 2005-2007 E90 323i sedan (Canadian market only)
• 2005-2007 E60/E61 523i sedan and touring (except USA market)
• 2006-2008 E85 Z4 2.5i roadster

150 kW Applications:

• 2010-2011 F10 523i sedan
• 2009-2011 E89 Z4 sDrive23i Z4 roadster (except North American market)

160 kW Applications:

• 2005-2009 E83 X3 2.5si (except USA market) sports activity vehicle
• 2005-2007 E60/E61 525i/525xi sedan and touring
• 2005-2008 E90/E91/E92/E93 325i/325xi sedan, coupe and touring (except North American market)
• 2006-2008 E85 Z4 2.5si roadster

N52B30

N52B30 from a BMW Z4 3.0si

The N52B30 2,996 cc (183 cu in) engine is available with four power outputs: 160 kW, 190 kW, 195 kW and 200 kW. Output variances are achieved by fitting different resonant intake manifolds and variations of engine management software.^[11] It was awarded as one of Ward's 10 Best Engines of the Year in 2006 and 2007.^[12]

160 kW Applications:

• 2005-2007 E90/E92/E93 325i/325xi sedan, coupe and convertible (North American markets only)
• 2009-2010 E84 X1 xDrive25i
• 2008-2011 E82/E88 125i coupe and cabriolet
• 2010-2011 F10 528i Sedan (North American markets only)^[13][14]

170 kW Applications:

• 2008-2011 E82/E88 128i coupe and cabriolet^[15] (North America only)
• 2007-2011 E90/E91/E92/E93 328i (North America only)
• 2008-2011 E60/E61 528i/528xi sedan and touring (North America only)

190 kW Applications:

• 2009-2011 E89 Z4 sDrive30i/3.0si roadster
• 2009-2010 E84 X1 xDrive38i sports activity vehicle
• 2010-2012 E87 130i hatchback
• 2005-2008 E90/E92/E93 330i/330Ci/330xi sedan, coupe and convertible (330i/330xi US models)
• 2005-2007 E60/E61 530i/530xi sedan and touring
• 2004-2007 E63/E64 630i coupe and convertible
• 2005-2008 E65/E66 730i sedan
• 2009-2011 F25 X3 xDrive28i^[16]

195 kW Applications:

• 2006-2009 E87 130i hatchback
• E85/E86 Z4 3.0si roadster and coupe

200 kW Applications:

• 2007–present E83 X3 3.0si sports activity vehicle
• 2006-2007 E70 X5 3.0si sports activity vehicle

See also

• BMW engines
• BMW vehicles

References

External links

• 's-new-six-cylinder-engines-in-depth WorldCarFans.com - BMW's New Six-Cylinder Engines - In Depth