Production 2004–2015 | ||
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Manufacturer BMW, Bayerische Motoren Werke AG | ||
The BMW N52 is a straight-6 DOHC piston engine which was produced from 2004-2015. It debuted on the E90 330i and E63 630i. In European markets, it began to be phased out following the release of the N53 in 2007. However, in markets such as North America, Australia or Malaysia, the N53 was deemed unsuitable due to the high levels of sulfur in the fuel. Therefore, the N52 remained in production until its replacement by the N20 turbocharged 4-cylinder engine in 2015.
Contents
Compared with its M54 predecessor, the N52 features variable valve lift (called Valvetronic by BMW), a lighter block due to the use of a magnesium alloy and an electric water pump and a variable oil pump. Like the M54, the N52 uses an electronic throttle control, variable valve timing to both camshafts (called dual VANOS by BMW) and a infinitely variable length intake manifold (called "DISA" by BMW). Later BMW changed the technology to a dual intake technology for later car models but kept the name DISA.
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, and 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.
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.
Hydraulic valve adjuster problems
The ticking noise of Hydraulic valve adjuster is a known problem with the N52 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 procedure seems not to resolve the matter. The second attempt to solve this problem is a replacement with improved HVA parts, however this procedure 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, 2008 have already been fitted with the improved cylinder heads that resolve this HVA problem.
N52B25
130 kW Applications:
150 kW Applications: 2007-2011BMW E90[ 323i (for Canadian market only)
160 kW Applications:
N52B30
Output variances are achieved by fitting different resonant intake manifolds and variations of engine management software.
The N52B30 was awarded as one of Ward's 10 Best Engines of the Year in 2006 and 2007.
160 kW Applications:
170 kW Applications:
190 kW Applications:
195 kW Applications:
200 kW Applications: