BMW N42B20 engine - information and work

The N42B20 engine has been in production since 2001 and distribution ended in 2004. The main goal of introducing this unit was to replace old versions of engines, such as M43B18, M43TU and M44B19. We present the most important information about the bike from BMW.

N42B20 engine - technical data

The production of the power unit was carried out by the BMW Plant Hams Hall plant, which existed from 2001 to 2004. The engine uses four cylinders with four pistons each in a DOHC system. The exact engine displacement was 1995 cc.

The in-line unit was characterized by a diameter of each cylinder reaching 84 mm and a piston stroke of 90 mm. Compression ratio 10:1, power 143 hp at 200 Nm. The order of operation of the N42B20 engine: 1-3-4-2.

For proper use of the engine, 5W-30 and 5W-40 oils were needed. In turn, the capacity of the substance tank was 4,25 l. It had to be replaced every 10 12. km or XNUMX months.

In which cars was the BMW unit installed?

The N42B20 engine was installed on models that are very well known to all automotive enthusiasts. We are talking about cars BMW E46 318i, 318Ci and 318 Ti. The naturally aspirated unit received positive reviews and is still on the road today.

Weight reduction and torque optimization - how was this achieved?

This unit uses an aluminum engine block. To this were added cast-iron bushings. This is an alternative solution for a fairly commonly used system made entirely of cast iron. This combination resulted in lighter weight compared to older BMW inline-four engines.

Torque optimization is achieved through the use of an electronically controlled variable geometry intake manifold. The system was called DISA and also improved power parameters at low and high speeds. Also added to this is the Bosch DME ME9.2 fuel injection system.

Basic design decisions

Inside the cylinder block are a completely new crankshaft with a stroke of 90 mm, pistons and connecting rods. The N42B20 engine also had balance shafts of the same design as the M43TU engine.

A 16-valve DOHC head, also made from this material, sits on an aluminum block. It was a real technological leap, as earlier models of motorcycles used only 8-valve SOHC heads. 

The N42B20 also includes Valvetronic variable valve lift and timing chain. Also, the designers decided to install two camshafts with a variable valve timing system - the Double Vanos system. 

Drive Unit Operation - Most Common Problems

One of the most common motorcycle problems is overheating. Usually this was due to contamination of the radiator. The best preventative measure was regular cleaning. A damaged thermostat can also be the cause - here the solution is a regular replacement every 100 XNUMX. km. 

Valve stem seals are also subject to wear, they stop working and, as a result, engine oil consumption increases. There are also problems associated with the cooling system. The N42B20 engine can also be noisy - the solution to the inconvenience associated with noise is to replace the timing chain tensioner. This should be done at 100 km. 

It is also necessary to monitor the condition of the BREMI ignition coils. They can fail when replacing spark plugs. In this case, replace the coils with EPA ignition coils. An engine oil recommended by the vehicle manufacturer is also essential for proper motorcycle operation. Failure to do so will require an overhaul of the assembly and replacement of the Vanos system. 

N42 B20 engine - is it worth choosing?

Motor 2.0 from BMW is a successful unit. It is economical and the individual repairs are relatively inexpensive - the market has a high availability of spare parts, and mechanics usually know the characteristics of the engine very well. Despite this, the unit requires regular inspection and careful maintenance.

The device is also suitable for chip tuning. After purchasing the appropriate components, such as a cold air intake, Cat Back exhaust system and engine management tuning, the modification allows you to increase the power of the unit to 160 hp. For this reason, the N42B20 engine may be a good solution.