BMW Mini – Timing Chain Failure

The BMW Mini range from 2010 onwards is affected by the same premature timing chain failure that has plagued the BMW Series 1, 3 and 5 models, in both the petrol and diesel ranges.

The timing chain has design faults; firstly, it is located at the rear of the engine bay and is not intended to be a serviceable part. Secondly, it stretches and weakens over time – and ultimately snaps, causing significant engine damage.

The table below details the affected BMW Mini models and engine codes:

BMW / Mini ModelYear RegisteredEngine Codes
Mini Cooper SD (R56)
Mini Cabrio Cooper SD (R57)
Mini Coupe Cooper SD (R58)
Mini Roadster Cooper SD (R59)
Mini Countryman Cooper SD (R60)
Mini Paceman Cooper SD (R61)
2010, 2011, 2012, 2013, 2014, 2015

N47C16A
N47C20A

Mini One D
Mini 1.5d
2015, 2016, 2017, 2018, 2019, 2020
2021, 2022
B37
Mini
120d & 125d, 218d, 220d & 225d
316d, 318d & 320d
418d
X1 25d
X5 25d
Mini Cooper SD
2015, 2016, 2017, 2018, 2019, 2020
2021, 2022
B47
Mini Clubman 1.5 Petrol
Mini Cooper 1.5 Petrol
2015, 2016, 2017, 2018, 2019, 2020
2021, 2022, 2023, 2024
B38
225i
320i
330i
Mini Cooper S
Mini Cooper JCW
Mini Clubman 2.0 Petrol
2015, 2016, 2017, 2018, 2019, 2020
2021, 2022, 2023, 2024
B48

What Happens When A Timing Chain Snaps?

When a BMW engine timing chain snaps, the inlet and exhaust valves collide with the pistons, resulting in massive engine damage. This damage can include blown pistons, bent valves, shattered rocker arms, snapped or bent camshaft, snapped or bent crankshaft & damaged camshaft housing.

Our Engine Rebuild Service

We have rebuilt over two thousand damaged BMW engines. Typically damaged by timing chain failure but also by water ingress, oil starvation, swirl-flap failure and various other causes. We have developed a thorough, highly successful engine rebuild procedure.

Identifying & repairing the catastrophic engine damage is a labour intensive and expensive job. The timing chain is located at the rear of the engine, therefore we must remove the entire engine and completely strip down all components to discover and replace all damaged parts to ensure we restore the engine to perfect running order.

We only perform full factory specification rebuilds using genuine OEM parts. The engine is rebuilt with modified chains, guides and tensioners – supplied by BMW, to reduce the risk of a repeat failure.

Engine Rebuild Costs

If your engine has been damaged by a snapped timing chain, you will require the full engine rebuild procedure, inclusive of BMW parts.

  • Engine Code: N47C16A rebuild cost will be £3,000.00 – £4,000.00 + VAT
  • Engine Code: N47C20A rebuild cost will be £3,000.00 – £4,000.00 + VAT
  • Engine Codes: B37 & B47 rebuild cost will be £4,000.00 – £6,000.00 + VAT
  • Engine Codes: B38 & B48 rebuild cost will be £4,000.00 – £6,000.00 + VAT

Whatever the cause of engine damage, each engine is individually stripped and assessed – depending on damage to engine parts, and fluctuations in BMW component pricing, the price may be higher.

Our engine rebuilds are covered by a 12 month warranty.

Cheaper Engine Repair Options

If you are considering other companies offering so called ‘re-manufactured’ engines at under £2,000, our advice is to steer clear – or do some thorough research. It is likely these engines are not rebuilt, nor re-manufactured – as genuine BMW replacement parts cost over £1,200 for the N47 engine variant.
It is more likely that the replacement engine will have been recovered from a damaged car – it’s also likely that it won’t have the modified BMW replacement timing chains, guides and tensioners – so they will just snap again…

It is a skilled and time consuming process to correctly repair an engine damaged by a broken timing chain, cheap solutions will not provide the reliability and 12 month warranty offered by Prestige.