M40B16 Engine Specifications
| Manufacturing | Steyr Plant |
| Engine make | M40 |
| Years of manufacture | 1988-1994 |
| Cylinder block material | cast iron |
| Power system | injector |
| Type | row |
| Number of cylinders | 4 |
| Valves per cylinder | 2 |
| Piston stroke, mm | 72 |
| Cylinder diameter, mm | 84 |
| Compression ratio | 9 |
| Engine displacement, cc | 1596 |
| Engine power, hp/rpm | 100/5500 102/5500 |
| Torque, Nm/rpm | 141/4250 143/4250 |
| Fuel | 92 |
| Environmental regulations | – |
| Engine weight, kg | ~132 |
| Fuel consumption, l/100 km (for 316i E36) – city – highway – mixed. |
10.2 6.1 7.5 |
| Oil consumption, gr./1000 km | to 1000 |
| Engine oil | 0W-30 0W-40 5W-30 5W-40 10W-40 15W-50 |
| How much oil in the engine, liters | 4.0 |
| Oil change is carried out, km | 7000-10000 |
| Engine operating temperature, deg. | 90-95 |
| Engine life, thousand kilometers – according to the factory data – in practice |
– 300+ |
| Tuning, hp. – potential – without loss of resource |
150+ n.d. |
| Motor installed | BMW 316i E30 BMW 316i E36 |
Reliability, problems and repairs of the BMW M40B16 engine
Low-volume inline four-cylinder engine series BMW M40, was released in 1988 and was developed on the basis of the M40B18, which was installed a crankshaft with a smaller stroke (was 81 mm) and other pistons, connecting rods remained the same. The M40 1.6 differs from the 1.8 in terms of intake manifold, throttle body, plugs and ECU. The cylinder head has not changed, the same 8-valve with a single camshaft (SOHC), with hydrocompensators valve clearances. Diameter of inlet valves is 42 mm, exhaust valves 36 mm. Characteristics of camshafts M40: phase 244/244 lift 10.6/10.6 mm.
The timing belt drive, the belt itself is not too reliable and does not have the proper width, so it has a low resource. On average, replacement of the timing belt and roller on the M40 is required every ~40 thousand kilometers, otherwise the engine will bend the valves in case of breakage.
This motor was used on BMW cars with index 16i.
The replacement for the engine appeared in 1993, in the face of the new M43B16 and within two years, the 1.6-liter M40 completely gave way to the updated power unit.
Modifications of the BMW M40B16 engine
1. M40B16 (1988 – 1991) – basic variation of the engine without catalyst, power 102 hp at 5500 rpm, torque 143 Nm at 4250 rpm.
2. M40B16 (1991 – 1994) – version with catalytic converter, power 100 hp at 5500 rpm, torque 141 Nm at 4250 rpm.
Problems and disadvantages of BMW M40B16 engines
Despite its reliable performance and clever design, the M40b16 engine has a number of problems:
- Motor knocking. The cause of the malfunction lies in a worn camshaft, hydrocompensators, rocker arm. The problem catches up with the car owner after 200 000 km of mileage. It is important to periodically check these elements and, if necessary, carry out timely replacement.
- Swimming revs. As a rule, the cause is air inflow when there is a crack in the air duct on the DMRV. If on inspection there is no visible damage, it is recommended to check the mass air flow sensor (aka DMRV), throttle valve, lambda probe. In rare cases, the revs may float due to heavy rotation of the camshaft.
- Drops during acceleration. BMW M40B16 owners note that the cause of the defect is the injectors, which need cleaning or replacement.
- Motor overheating. The cause of the malfunction should be sought according to a standard, established plan. To begin with, you should check the coolant level, inspect the radiator and plastic elements for cracks, assess the condition of the thermostat, the pump, air plugs.
- If the BMW M40B16 does not want to start, you should pay attention to the work of the gasoline pump, spark plugs or ignition coil, wires, fuel system as a whole.
- The timing chain. Perhaps this problem is the most common and annoying shortcoming. This part of the engine is characterized by a low level of reliability, weakness, low resource. With the service life on other internal combustion engines, where the chain works more than 200,000 km, on the m40b16 the service life of the element is about 40,000 km. In this regard, it is important to monitor the condition of the timing chain and carry out its timely replacement.
In addition, do not forget that the M40B16 engines are not produced in factories for a long time, so it is impossible to meet a new copy in the car market.
Tuning BMW M40B16 engine
Stroker
It is necessary to specify at once, tuning of M40 is far not the most profitable and successful investment of means, it is much easier to buy a contract engine BMW M50 for example, to weld and to know no troubles.
If your hands are stretched to refine your 1.6 liter, then stroker is your choice. To increase the volume up to 2.1 liters you need to buy a crankshaft from M47D20 (stroke 88 mm), S50B30 pistons, connecting rods M44B19. The cylinder head, timing, intake, exhaust, ECU from M44 (or M42). All this together, together with boring the block to 86 mm, will give 150-160 hp.
To turbocharge or blow into the M40 with a compressor is even more expensive and crazy, only the cylinder block will remain factory, and at the output we will get not too much power and lack of reliability.
MOTOR RATING: 4-