BMW N46B18 engine
The youngest version of the N46 powertrain line - N46B18, was created on the basis of the N46B20 and has been produced since 2004, and only for BMW E46 316 cars. In mid-2006, in connection with the introduction of the BMW E90, all E46 models were completely removed from the assembly line , and this engine did not have time to get mass distribution.
N46B18 was originally intended as a replacement for its predecessor - N42B18, and received a modified crankshaft, modified balance shafts and connecting rods, as well as completely different ones: a cylinder head cover and a timing chain tensioner. The N46B18 had (new): intake manifold, alternator and spark plugs.
Unlike the standard N46, its 1.8-liter variation had: a crankshaft that received a short stroke (81 mm); pistons under compression ratio 10.2; conventional collector - without DISA. Valvetronic was integrated into the Bosch ME 9.2 system.
The N46B18 power plant, like its 2-liter version, has a number of related models created almost on the same base.
In 2011, the N46B18, however, as well as the rest of the in-line gasoline “fours” from BMW, was replaced by a brand new turbocharged N13B16 engine, which has been produced in various modifications up to the present.
Key features of the BMW N46B18
| Volume cm3 | 1796 |
|---|---|
| Max power, hp | 116 |
| Max torque, Nm (kgm)/rpm | 175 (18) / 3750 |
| Consumption, l / 100 km | 7.8 |
| A type | Inline, 4-cylinder, injector |
| Cylinder diameter, mm | 84 |
| Max power, hp (kW)/r/min | 116 (85) / 5500 |
| Compression ratio | 10.2 |
| The piston stroke, mm | 81 |
| Models | 316i E46 |
| Resource, outside. km | 250+ |
Reliability and disadvantages of N46B18
pros
- Intake manifold
- Exhaust camshaft
- Swap Potential
Cons:
- Increased consumption and oil leaks
- Engine noise, vibration
- Problems with Valvetronic, oil pump, CVCG and vacuum pump
The main reason for the appearance of an oil burner in the N46B18, as in the 42nd engine, is the use of low quality engine oil. Also, the problem may be in failed valve seals.
This mainly happens after a run of 50-100 thousand km. Oil not recommended by the manufacturer entails additional problems. For example, with the same Valvetronic, oil pump, crankcase ventilation valve and so on. In this case, saving on maintenance is definitely not worth it.
Also, after a run of 50 thousand km, the cylinder head gasket and vacuum pump will most likely be asked for replacement.
The causes of vibration and unnatural engine noise usually lie either in the timing chain tensioner or in a stretched chain. After a run of 100-150 thousand km, such problems are not at all uncommon.
To reduce the likelihood of problems with the engine, it is advisable to change the oil on time, or even more often, which must be original and recommended by the manufacturer. In addition, it is important to pour good gasoline and undergo maintenance in a timely manner.
Tuning potential
Also, like other small displacement 4-cylinder ICEs, the N46B18 is good for swap, but it is completely unsuitable for tuning and the only adequate way to increase power in the case of it will be chip tuning. Most likely, a zero-resistance filter will be installed in the tuning studio, which will be led to the front bumper, the catalyst will be cut out and the system will be completely re-flashed. All this will add to the dynamics and get +10 hp. For something more, you have to put the engine on 6 cylinders.
