Mercedes CLA M270/M282/OM651 Engine SolutionsUK Specialists

A Mercedes Benz CLA replacement engine typically costs between £1,500 for a used unit and £4,500 for a rebuilt diesel, with AMG variants reaching £11,000. Specialist fitting adds £450-£800.

• Used CLA engines: £900-£2,200 depending on mileage and engine code
• Rebuilt OM654/N47 diesel units: £2,000-£4,200 supply only
• M133/M139 AMG rebuilt engines: £4,500-£11,000
• Specialist fitting adds £450-£800; dealer labour significantly higher
• 12-month warranty included on all rebuilt units through EngineMarket

The CLA 220d uses two different engines. Pre-2019 N47D20C (BMW-sourced) has well-documented timing chain tensioner failure between 60k-100k miles. Post-2019 OM654 is more reliable but has NOx sensor and cold start issues.

• N47D20C timing chain rattling on cold start signals imminent tensioner failure
• OM654 (2019+) owners report rough idle/shaking for 30 seconds on cold starts - Mercedes calls this "normal characteristic"
• NOx sensor failures common on OM654, requiring cleaning or replacement every 10k-15k miles
• EGR cooler cracks affect both engine families, causing coolant loss
• 220d is most searched CLA diesel for replacement due to N47 timing chain reputation

Well-maintained CLA diesel engines (OM651/OM654) regularly reach 150,000-200,000 miles. Petrol M270/M260 units typically last 120,000-150,000 miles. N47D20C diesels often fail earlier due to timing chain tensioner weakness.

• OM651 2.1L diesel (2013-2015): 180k+ miles with regular servicing
• OM654 2.0L diesel (2019+): too new for full data but promising design
• N47D20C (2015-2019): timing chain often fails 60k-100k miles - preventative replacement extends life
• M270 petrol: 120k-150k miles; HPFP failure common after 80k
• Regular oil changes every 10k miles (not Mercedes' 15k-18k interval) significantly extends life

The 2015-2019 CLA 220d with the N47D20C engine carries the highest risk due to timing chain tensioner failure. Early 2013-2015 CLA 250 petrol units also show higher complaint rates for HPFP and timing issues.

• N47D20C (CLA 220d 2015-2019) is most discussed for catastrophic chain failure
• 2014 CLA 250 has more owner complaints than any other year, including blown engine reports
• M270 petrol HPFP failure sends metal debris through fuel system - costly repair
• OM607 1.5L diesel (CLA 180d) is underpowered but mechanically robust
• Post-2019 OM654 and M282 engines show fewer major failures but have NOx sensor annoyances

Timing chain replacement on a CLA costs £1,400-£1,900 at a specialist or £2,200-£2,800 at a main dealer. This is preventative work. If the chain has already slipped, full engine replacement at £2,800-£3,800 is required.

• Specialist preventative chain/tensioner replacement: £1,400-£1,900 including gearbox removal
• Dealer pricing for same work: £2,200-£2,800
• Labour-intensive because chain is at rear of engine on most CLA diesels
• Rattling noise on cold start for 1-2 seconds is the early warning sign
• Once timing jumps, valves contact pistons - engine is beyond repair

Yes, if the car is otherwise sound. A CLA worth £4,000-£7,000 with a failed N47 diesel justifies a £2,800-£3,800 rebuilt engine. For older, high-mileage petrol models, used engine at £1,200-£2,200 is often the smarter financial choice.

• CLA 220d with good body/interior: replacement engine is cost-effective
• CLA 180 or 200 petrol with 120k+ miles: consider used engine over rebuilt
• AMG CLA 45: always worth rebuilding - cars hold strong value
• Specialist rebuilt engines fix original design weaknesses and include warranty
• Compare against £4,000-£5,000 main dealer new engine quotes

2013-2015 models suffer OM651 chain stretch and M270 HPFP failure. 2015-2019 CLA 220d N47D20C is worst for timing chain tensioner failure. 2019+ models have OM654 cold start misfire/shaking and NOx sensor faults, plus M260 oil consumption.

• 2013-2015 (OM651 diesel): timing chain can stretch - listen for metallic clatter
• 2014 (CLA 250 petrol): highest complaint volume including engine failure
• 2015-2019 (N47D20C diesel): timing chain tensioner failure 60k-100k miles
• 2019-2023 (OM654 diesel): cold start shaking/misfire for 30 seconds - dealer says "normal"
• 2019-2023 (M260 petrol): piston ring wear causing oil consumption

Yes, used CLA engines are a budget-friendly option at £900-£2,200. Ensure the donor engine has the exact same engine code (e.g., N47D20C not N47D20) and comes from the same generation C117 or C118.

• Used engines are 50-70% cheaper than rebuilt units
• Risk: unknown service history and hidden wear
• Only buy from breakers offering compression test results
• Match engine code exactly - M270 has 1.6L and 2.0L variants
• 30-90 day warranty typical; less protection than 12 months on rebuilt

Every rebuilt engine supplied through EngineMarket includes a minimum 12-month unlimited mileage warranty covering parts and workmanship. Premium suppliers offer 24-36 month warranties on remanufactured units.

• 12-month unlimited mileage is standard on all rebuilt CLA engines
• Remanufactured engines often carry 24-36 month coverage
• Warranty covers internal component failure, not external ancillaries
• Supply & fit packages include labour warranty through fitting specialist
• Always confirm exact terms - some warranties exclude timing chain (but ours don't)

Diesel OM651 (2013-2015) is most robust but older. OM654 diesel has cold start quirks but no major failures. Petrol M270 suffers HPFP failure; M260 has oil consumption. Neither fuel type is clearly more reliable - condition and maintenance matter more.

• Pre-2015 OM651 diesel: chain stretch possible but otherwise solid
• N47D20C diesel (2015-2019): timing chain risk - avoid without proof of replacement
• OM654 diesel (2019+): NOx sensor issues, cold start shaking - not mechanical failure
• M270 petrol: HPFP failure contaminates entire fuel system
• For high mileage (15k+ annual), diesel economy wins; for short journeys, petrol avoids DPF issues