6 Common BMW B47 Diesel Engine Problems (20d & 25d)

We’ve talked about BMWs N47 engine before, and we all know it’s not exactly the best BMW diesel out there. In search of fewer problems, a lot of BMW buyers tend to turn towards its newer brother, the B47 engine.

This article will reveal all the common BMW B47 engine problems.

Doing your own homework when it comes to purchasing a used car, especially a BMW is the right way to go. Sometimes BMW engines are perfect, while sometimes their engines can have a ton of expensive issues to fix. That’s why we are here to help you out by pinpointing these problems for you.

So, what will we cover in this article? First, we are going to learn the basic BMW B47 engine specs and learn the numbers this engine is making. Then, we are going to cover the common BMW B47 engine problems and see what troubles this engine has. Lastly, we will discuss the applications of this engine. So, without further ado, let’s dive into the article.

Basic BMW B47 Engine Specs

The B47 is a diesel engine that was introduced by BMW in 2014. The B47 replaced the N47 engine that was previously produced. 

This new B47 engine is a part of BMW’s family of modular engines along with designs like the B38, B48, and B58.

This means that the B47 engine is a pretty new design with all the modern technologies. These technologies include the double overhead camshaft layout (DOHC) with four valves per cylinder. As well as a twin-turbo setup.

This engine complies with e Euro 6 standard and for this purpose, it has special AdBlue injection where special fluid is injected into the exhaust to further reduce emissions.

Does the B47 engine have swirl flaps?

Yes, the B47 engine does feature swirl flaps and they can cause problems down the road if the car isn’t properly maintained. More on this matter later.

Nevertheless, here are the full specs of the B47 engine.

  • Configuration: Inline-4
  • Displacement: 2.0L
  • Cylinder Bore: 84 mm
  • Piston Stroke: 90 mm
  • Block & Head Material: Aluminum Alloy
  • Head Design: DOHC, 4 valves per cylinder
  • Fuel Injection: Common Rail
  • Turbo: Single or Twin-Turbo
  • Compression Ratio: 16.5:1
  • Horsepower: 114 – 228 hp
  • Torque: 199 – 369 lb-ft (270 – 369 N-m)

Common BMW B47 Engine Problems

Common problems with the B47 engine include:

  • Intake Swirl Flap Jam
  • Timing Chain Stretch
  • EGR Cooler Leak
  • Clogged DPF
  • Fuel Injector Failure
  • Turbocharger Failures

Now that we listed the common B47 engine problems, we can move on and further elaborate on these issues.

Knowing when and how these issues appear is really important if you want to recognize a certain problem. So, follow us closely while we elaborate on everything thoroughly in the following chapters.

Intake Swirl Flap Jam

The first problem on our list is connected to the intake swirl flaps. So, what are intake swirl flaps, and why are they important?

Well, in gas-powered engines, you have the throttle body, which is the component that allows air to enter the intake manifold.

In diesel engines, we don’t have throttle bodies since they are not necessary. Diesel ignites via compression.

So, instead of using a throttle body, diesel engines are using simple flaps that open and close. These flaps are mounted on the intake and they are activated by an electronic actuator.

Diesel engines love to run dirty and this way of running simply clogs up these flaps, preventing them from opening and closing correctly. Thus, letting no air into the engine and inability to run properly.

The flaps simply jam and malfunction. In this case, your best bet would be to replace the intake manifold with a new one or remove them completely. Removing them could affect your fuel economy. So, beware of this repercussion.

Timing Chain Stretch

Timing chain stretch is a problem on the B47 engine. A lot of people don’t think that this is the case but it actually is and there are a lot of reports on the problem.

The timing chain is a component that has a limited lifespan and its lifespan depends a lot on the maintenance that you give to the engine.

So, if you very rarely change your oil, the life of the timing components will take a toll and they will fail more frequently.

Although, this chain specifically is by design prone to stretching since there are a lot of complaints on this issue. Just like in the case of the N47 engine.

This is why whenever you notice rattling noises from the timing cover, it is important to take this seriously and replace the timing chain before the chain jumps and creates more problems.

EGR Cooler Leak

There was also a problem with the EGR on this engine. In fact, there was even a recall of the EGR cooler on the B47 engine issued by the NHTSA.

The EGR could develop an internal coolant leak. This leak of coolant along with the soot can mix together and create flammable deposits.

These flammable deposits could burn your car to the ground. The affected models are the BMW F02 and the F25 chassis codes with the B47 engine.

Now let’s move to the next BMW B47 engine problems.

Clogged DPF

Problems with the DPF filter were also noted. So, what is a DPF, and why is it a problem with this engine?

DPF stands for Diesel Particulate Filter. This filter is installed in every modern diesel vehicle that is sold.

This filter simply collects the soot that is created in the exhaust gasses and traps this soot. Then, when the DPF is full, it needs to regenerate.

This regeneration is a process that every owner should do. Many owners don’t, and they clog up their DPF.

The solution is manual cleaning or replacement of the DPF, both processes are fairly expensive to do. So, drive your car on the highway more frequently to regenerate this component.

To make sure this doesn’t happen to you, read our guide on how to drive and maintain a diesel engine to prevent engine problems.

Fuel Injector Failure

Fuel injectors are also common on these diesel engines. For those who don’t know, modern diesels all use complex common rail fuel injection.

This system uses very sophisticated injectors that are prone to failure. No matter how good the injector is, its lifespan is not more than 150,000 miles (ca. 241,402 km) in many cases.

So, sooner or later they will clog up or will start to leak diesel. That’s why you need to be aware of this if you plan to get a used diesel car. These injectors can be very expensive to replace or refurbish.

Turbocharger Failures

And last but not least is the turbocharger failure. This engine uses either a single or a twin-turbo setup.

Turbochargers have a limited lifespan of 150,000 miles (ca. 241,402 km) before they start to fail. They will start to create whistling noises and will eventually completely fail, resulting in a complete loss of power.

The way around this problem is to replace or refurbish the turbo on your B47 engine. Also, a very expensive thing to do.

What Cars Have the B47 Engine?

The following BMW models have the B47 engine:

B47D20 (85 kW)

  • 2015 – 2019 BMW F30/F31 316d

B47C/D20 (110 kW)

  • 2014 – 2016 BMW F10 518d
  • 2014 – Present BMW F45 218d Active Tourer
  • 2014 – Present BMW F46 218d Gran Tourer
  • 2015 – 2019 BMW F20 118d
  • 2015 – 2019 BMW F22 218d
  • 2015 – 2017 BMW F25 X3 sDrive18d
  • 2015 – 2019 BMW F30/F31/F34 318d
  • 2015 – 2020 BMW F32/F36 418d
  • 2015 – 2022 BMW F48 X1 sDrive18d
  • 2015 – 2023 Mini F54 Cooper D Clubman
  • 2017 – Present BMW F39 X2 sDrive18d
  • 2017 – Present Mini F60 Cooper D Countryman
  • 2018 – 2023 BMW G30 518d
  • 2019 – Present BMW G20 318d
  • 2019 – Present BMW F40 118d

B47C/D20 (120 kW)

  • 2015 – Present Mini F56 Cooper SD
  • 2015 – 2018 BMW F30 320d Efficient Dynamics Edition

B47C/D20 (140kW)

  • 2014 – 2016 BMW F10/F11 520d
  • 2014 – 2018 BMW F26 X4 xDrive20d
  • 2014 – Present BMW F45 220d Active Tourer
  • 2014 – Present BMW F46 220d Gran Tourer
  • 2015 – 2019 BMW F20 120d/120d xDrive
  • 2015 – 2021 BMW F22/F23 220d
  • 2015 – 2017 BMW F25 X3 sDrive20d/xDrive20d
  • 2015 – 2019 BMW F30/F31/F34 320d
  • 2015 – 2020 BMW F32/F36 420d
  • 2015 – 2022 BMW F48 X1 sDrive20d
  • 2015 – 2023 F54 Mini Cooper SD Clubman
  • 2016 – 2023 BMW G30/G31 520d
  • 2017 – Present BMW F39 X2 xDrive20d
  • 2017 – Present F60 Mini Cooper SD Countryman
  • 2017 – Present BMW G01 X3 xDrive20d
  • 2018 – Present BMW G02 X4 xDrive20d
  • 2018 – 2023 BMW G32 620d Gran Turismo
  • 2019 – Present BMW G20 320d
  • 2019 – Present BMW F40 120d xDrive
  • 2019 – Present BMW F44 220d Gran Coupe
  • 2021 – Present BMW G42 220d

B47C/D20 (165 kW)

  • 2015 – 2019 BMW F20 125d
  • 2015 – 2019 BMW F22 225d
  • 2015 – 2018 BMW F30/F31/F34 325d
  • 2016 – 2020 BMW F32/F33/F36 425d

B47C/D20 (170 kW)

  • 2018 – Present BMW G05 X5 xDrive25d
  • 2015 – 2018 BMW F15 X5 sDrive25d/xDrive25d
  • 2016 – 2022 BMW F48 X1 xDrive25d
  • 2017 – 2019 BMW G30/G31 525d
  • 2018 – Present BMW F39 X2 xDrive25d
  • 2016 – 2019 BMW G11 725d/Ld

FAQ

What Problems does The BMW B47 engine have?

Common problems with the B47 engine include the timing chain stretching, EGR cooler failure on some models, DPF clogging up, turbocharger failure, and intake swirl flap failure.

Is The BMW B47 Engine Reliable?

This engine is fairly reliable. Except for the issues with the timing chain that tends to stretch. This is a common problem with this engine. Another problem is the situation with the EGR cooler leaking coolant. Besides that, just normal diesel issues happen on higher miles like swirl flap failure, injector failure, and turbo failures.

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