BMW M40B18 Engine Specs, Problems & Reliability

BMW M40B18 Engine – Here in this post, I have taken all the details about BMW M40B18 Engine from the (official site) including BMW M40B18 Engine specs, Weight, Price & Dimension.

We believe to provide accurate details to our readers and we prefer only official sources for information about BMW M40B18 Engine.

All the details which you want to know about BMW M40B18 Engine you can find in this article which is updated.

BMW M40B18 Engine

The engine is traditional and straightforward. Cast iron is used to make the cylinder block. The cylinder head houses a SOHC 8-valve aluminum cylinder head with hydraulic lifters. The M40B18 camshaft is 244/244 degrees (single-pattern) and has a valve lift of 10.6/10.6mm.

Contrary to M10 engines, the M40 engines use a timing belt, not a chain. The engine includes an aluminum intake manifold and electronic fuel injection and ignition. Bosch Motronic 1.1.7 fuel injection system is used for E30 cars.

The M40B18 application covers the 18i variants. This engine was not produced after BMW spent two years designing a replacement engine called the M43B18.

BMW M40B18 Engine

BMW M40B18 Engine Specs

M40-series was created in 1987 with the M40B18 1.8-liter four-cylinder engine. The M40 engine replaced the M10 series.

It was trendy and was common in BMW models back then. The manufacturer then released the smaller version, the 1.6-liter M40B16 engine.

ManufacturerSteyr Plant
Production years1987-1994
Cylinder block materialCast Iron
Cylinder head materialAluminium
Fuel typeGasoline
Fuel systemFuel injection
Number of cylinders4
Valves per cylinder2
Valvetrain layoutSOHC
Bore84.0 mm
Stroke81.0 mm
Displacement1796 cc
Type of internal combustion engineFour-stroke, naturally aspirated
Compression Ratio9:1
Power113 hp at 5,500 rpm
Torque120 lb-ft (160 Nm) at 4,250 rpm
Firing order1-3-4-2
Engine oil weight5W-30, 5W-40, 10W-40, 15W-50
Engine oil capacity4.0L
Oil change interval6,000 miles (10,000 km) or 12 months
ApplicationsBMW 318i E30, BMW 318i E36, BMW 518i E34

BMW M40B18 Engine Problems & Reliability

Timing belts are the main problem. It wears quickly and can cause bent valves. It would help if you always looked for signs of damage to your timing belt.

Broken hydraulic lifters or camshafts can produce tickling and knocking sounds. To avoid costly repairs in the future, it is essential to replace any damaged camshaft. A worn camshaft will cause the engine not to rev as high.

Old electronic components are often found in older engines such as the M40B18. Check the oxygen and air flow sensor if the idle is unstable or acceleration problems persist.

Dirty injectors are a common problem that can lead to fuel consumption and power loss.

The M40 is also sensitive to heat, as are all BMW engines. Make sure to check the maintenance schedule and clean the radiator.

The M40B18’s engine life is approximately 180,000 miles. The engine is reliable, but finding a car with this engine and low mileage is challenging.

BMW M40B18 Engine FAQs

What is the BMW M40B16?

The M40 engine replaced the M10 series. This was a very popular and widespread model for BMWs in those days. The smaller M40B16 engine, a 1.6-liter version, was released a year later.

What kind of engine does a BMW M40 have?

M40-series was created in 1987 with the M40B18 1.8-liter four-cylinder engine. The M40 engine replaced the M10 series. It was very popular and common in BMW models back then. The smaller M40B16 engine, a 1.6-liter version, was released a year later. It is simple and traditional.

Why did BMW stop making The M40B18?

The M40B18 application applies to 18i models. This engine was discontinued in 1994, as BMW was already producing a new engine for the next two years, the M43B18. 1. Timing belts are the main problem.

What is the difference between M40 and M40B18 engines?

The M40B18 engine with a 1.8-liter displacement was used in the design of the small engine. It has a longer stroke and a larger displacement. Cast iron cylinder blocks make this engine durable and reliable. The 1.6l M40 has a crankshaft with a smaller stroke than the M40B18 engine, but the connecting rods are the same (the length is 140mm).

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