The N52 was the last naturally-aspirated made by BMW and was listed as one of the world's 10 best engines in 2006-2007. Read on to discover why this engine is so love by Bimmer enthusiasts.
Introduction
By the mid-2000s, BMW had established a reputation for producing high-quality, naturally aspirated inline-six engines. It released the M54 (and the performance-oriented S54 shortly after) around the turn of the century, cementing itself as one of the finest in the field for the six-pot layout. What came next had to be better. Here comes the BMW N52.
From 2004 until 2015, the N52 was in production for nearly a decade. It was the first water-cooled engine to have a magnesium and aluminum composite engine block. It first appeared on the E90 3 Series and E63 6 Series, and then spread to other models in the company's portfolio. After eleven beautiful years, the N52 was the final naturally-aspirated engine produced by BMW before the complete range was converted to turbochargers.
It is also remembered as one of the most dependable BMW engines of the contemporary age. An engine that was named one of Ward's 10 Best Engines in 2006 and 2007. The BMW N52 is described in detail below
The N52 Was BMW'S Most Reliable Inline-Six
As previously stated, the N52 was the first BMW engine to be built of magnesium and aluminum. This was due to the manufacturer's desire to create a lighter engine without sacrificing durability. However, because magnesium corrodes more rapidly than aluminum, BMW came up with the brilliant notion of encasing an aluminum core in a magnesium shell. The end result? A German engineering marvel that attracted comparisons to the legendary 2JZ 'GE' from the far east.
Technology
The N52 has some huge shoes to fill after the triumph of the M54. BMW provided by including its Valvetronic (variable valve lift) system, an electronic water pump (rather than a mechanical one), a variable output oil pump, and the lightweight engine block described earlier. Certain features carried over from the M54, such as electronic throttle control and the company's twin VANOS system (variable valve timing).
Available Versions
The N52 was offered with two engine options: a 2.5L unit and a 3.0L one. The former was known as the N52B25, while the latter was known as the N52B30. The performance of these engines varied substantially
2.5L version
Between 2005 and 2011, the N52B25 was offered in three engine configurations. Depending on the application, power varied from 174 to 215 hp, with peak torque ranging between 170 and 184 lb-ft.
3.0L version
From 2006 until 2015, the N52B30 was available in seven different engine configurations. This 3.0L edition was the N52's most popular and longest-running variant. Peak power ranged from 215 to 268 hp, with peak torque ranging from 199 to 232 lb-ft. All N52B30 engine tuning had a bore x stroke measurement of 85x88mm and a compression ratio of 10.7:1. However, the intake manifolds and ECU were modified to generate differing peak values.
Which BMWs Use the N52 Engine?
The N52 engine was used in several models of BMW 3-Series, 5-Series, 6-Series, 7-Series, Z4, and X-Series
N52B25
The 2.5L N52B25 was used in a variety of models, including the E90 323i, E60/E61 523i, F10 523i, E83 X3 2.5si, many Z4 models, and others. From 2005 to 2011, it was used on the E90/E91/E92/E93 325i and 325xi; however, this model was never marketed in the United States or Canada.
N52B30
The most popular of the two engines, the 3.0L N52B30, was offered on a variety of vehicles. The E90/E92/E93 325i and 325xi, the E60/E61 525i and 525xi, the F01 730i, and the E87 130i are among them. The engine was utilized in the E83 X3, E70 X5, and E63/E64 630i from 2006 to 2013. This variant, at 268 horsepower, was the most powerful naturally aspirated, inline-six BMW engine on a non-M vehicle.
What Are The Most Common BMW N52 Engine Problems?
The N52 was in a class by itself when compared to inline-six engines or even other six-cylinder layouts from various manufacturers. It was a prize-winning example of German precision engineering that stood the test of time. The N52, like every mechanical device, had its share of problems, some more prevalent than others. Here are some things to check for if you're looking for a secondhand BMW with a N52 engine:
Ignition Coil Issues
Numerous N52 owners have suffered ignition coil problems on their engines. While some blame defective manufacturing coils, the underlying source of the problem is a combination of uneven maintenance and the usage of low-cost parts. If damaged coils are excluded, many failed owing to worn spark plugs, which pushed the coil to work extra to compensate for spark plug wear. If you're having ignition coil problems with your N52, we've published a comprehensive guide on how to diagnose and repair your ignition coils at home. It would be ideal if you had the necessary tools, some spare time, and the appropriate ignition coil parts.
Water Pump Failure
Apart from its predecessor, the M52, the N52 incorporated an electric water pump rather than a mechanical device. While this had several benefits, including the ability for the ECU to modify the flow rate based on how you drove, it was still a relatively new technology for the manufacturer. They were badly constructed, with multiple complaints of breakage as early as 40,000 miles. If your water pump malfunctions, you should observe overheating or vapor pouring from the radiator. The stock water pump has a plastic impeller, which should survive longer if replaced with a metal impeller.
VANOS Failure
BMW's variable valve timing system for the intake and exhaust valves, often known as double VANOS, is used in the N52. The technique consists of VANOS solenoids that regulate the oil flow to the actuators, which move the cam gears, allowing the valves to open and close. The failure of these solenoids was one of the most typical issues with the N52. In such a case, your engine will continue to function, but there will be a visible loss in power, as well as other indications such as a choppy idle. Fortunately, solenoids are a relatively inexpensive and labor-intensive component to repair. They typically last 70,000-75,000 miles, however we recommend replacing them on a regular basis to minimize sudden engine performance decreases.
Hydraulic Valve Lifters
The N52 has hydraulically adjustable valve lifters, which tend to wear out on higher usage engines. Many long-term owners complain about a 'ticking' noise coming from the engine, which is usually caused by worn-out valve lifters. It is especially noticeable at cold starts and before the engine has warmed up. A malfunctioning valve lifter has no significant impact on engine performance, but if left untreated, it can cause an irritating rattling. When there isn't enough oil reaching them to work properly, they 'tick.' Poorly made cylinder heads and lifters are the cause of this, and N52 engines made before 2008 are particularly susceptible to it. BMW revised the design of the lifters and cylinder head in 2009, although there are still allegations of post-2009 cars that have faced this issue.
Valve Cover Gasket Oil Leaks
A valve cover gasket oil leak is a problem that affects many BMW engines, not only the N52. Most of the time, it happens gradually as the heat from the engine wears out the gaskets and causes them to break. Regular maintenance inspections might assist to avoid this. The smell of burning oil, an oil leak, or smoke from the valve cover region may indicate that the gasket needs to be replaced.
Leak in the Oil Filter Housing The oil filter housing gasket, like the valve cover gasket, will degrade with time. The gasket connects the oil filter housing to the engine; if it splits, oil might spill. While all oil leaks must be repaired as soon as they are discovered, attention to an oil filter housing leak is critical since it can create significant mechanical difficulties if left unattended. If oil gets on the serpentine belt, it can cause it to slip and send pieces of it into the front crank seal and the engine. This can have disastrous results, such as a wrecked engine.
