BMW N53


The BMW N53 is a naturally aspirated straight-6 petrol engine which was produced from 2006 to 2013. The N53 replaced the BMW N52 in certain markets and debuted on the post-facelift E60 5 Series.
In European markets, the N53 began replacing its port-injected parent, the BMW N52, in 2007. Markets such as the United States, Canada, Australia, and Malaysia retained the N52, as the N53 was deemed unsuitable due to the high sulfur content of local fuel.
The N52 and N53 are the last naturally aspirated straight-six engines produced by BMW, ending a history of continuous production of this engine configuration since the BMW M30 in 1968. In 2011, the N52 began to be replaced by the BMW N20 turbocharged four-cylinder engine. N53 production ceased in 2013.
There is no BMW M version of the N53. The BMW N54 turbocharged straight-6 engine was produced alongside the N53.

Design

Compared with its N52 predecessor which was port-injected, the N53 uses direct injection. The direct injection system uses piezoelectric fuel injectors which inject into the combustion chamber, using a stratified lean mixture operation. The compression ratio was increased to 12.0:1 for the N53.
As per the N52, the N53 has double-VANOS and a magnesium alloy block. Unlike the N52, the N53 does not have Valvetronic, due to space limitations in the cylinder head.
The bore of and stroke of are the same as the N52. Each cylinder has coil-on-plug ignition, as per the N52.

Versions

N53B25

The version of the N53 produces and. It has a bore of and a stroke of.
Applications:
  • 2006-2010 E60/E61 523i

    N53B30 (150 kW)

A version of the N53 was used in the pre-facelift F10 523i.
Applications:
  • 2009-2011 F10/F11 523i

    N53B30 (160 kW)

This version of the N53 produces, the same figure as the version of its N52 predecessor. However, peak torque increased from.
Applications:
A version of the N53 was used in the pre-facelift F10 528i.
Applications:
  • 2009-2011 F10/F11 528i

    N53B30 (200 kW)

The most powerful version of the N53 produces of power and of torque.
Applications:
  • 2007-2010 E60/E61 530i
  • 2007-2010 E63 630i
  • 2007-2013 E90/E91/E92/E93 330i
  • 2011-2013 F10 530i

    High-Pressure Fuel Pump failures

The N53 uses the same High-Pressure Fuel Pump as the BMW N54 turbocharged straight-six engine, which had HPFP failures leading to Lemon Law "buy backs" and legal action in the United States. The N53 engine was not sold in the United States, therefore the N53 engine was not involved with these actions.
Failures of the N53 HPFP have been reported, although it is not known whether failure in the N53 is as common as the N54.