Engine Finders

Mercedes-Benz M-Class Specialists

Expert Solutions for Every M-Class – 250 CDI to AMG ML 63

Need a reliable replacement engine for your Mercedes-Benz M-Class?
Engine Finders specializes in M-Class engines with solutions for common OM642 injector failures and M113 timing issues across all variants.

Find Your Perfect Mercedes-Benz M-Class Engine Today!
Mercedes-Benz M-Class engine replacement specialists | Engine Finders

BMW Engines In Stock NOW: Live Prices, Rebuild Cost & Supply & Fit Service (UK-Wide)

Check REAL-TIME stock availability for all BMW models. View exact rebuild costs, professional engine works & find a certified garage near you - all with 12-month warranty, MoT-ready units, and same-day dispatch.

Mercedes-Benz M-Class Replacement Engines Options - Verified Units (UK Supply)

All engines bench-tested, VAT-inclusive, with 12-month warranty. MoT-compliant. Nationwide delivery. Direct OEM fitment for W163, W164, W166.

Mercedes-Benz M-Class Rebuilt Engines

Includes updated timing chain tensioners for M112/M113 V6/V8 reliability.

Mercedes-Benz M-Class Remanufactured Engines

Fully reconditioned to factory specs; ideal for OM612 and OM642 diesel variants.

Mercedes-Benz M-Class Reconditioned Engines

Restored with new head gaskets to address common M112 overheating issues.

Mercedes-Benz M-Class Replacement Engines

Direct-fit units for all W163/W164/W166 generations; plug-and-play installation.

Mercedes-Benz M-Class Refurbished Engines

Performance-tuned with upgraded turbochargers for OM642 diesel models.

Mercedes-Benz M-Class Used Engines

Verified low-mileage units; full service history and diagnostic report included.

Mercedes-Benz M-Class Compatible Engine Codes & Average Prices on Rebuilt Units

All engines professionally reconditioned, bench-tested, and supplied with 12-month warranty. Direct OEM fitment. VAT-inclusive. Nationwide UK delivery.

Where to buy Mercedes-Benz M-Class replacement engine | Engine Finders

Why Choose Engine Finders for Your Mercedes-Benz M-Class Engine?

Engine Finders connects UK drivers with vetted specialists for reliable, reconditioned Mercedes-Benz M-Class replacement engines. From the OM612 and OM648 inline-five and inline-six diesels to the M113 V8 and M272 V6 petrol engines found across both W163 (1998–2005) and W164 (2005–2011) generations, we address series-wide failure patterns that affect all M-Class variants. Whether you're battling OM648 injector seal leaks common to ML270/320 CDI models or M113 timing chain guide degradation across early ML55 AMG units, Engine Finders makes it easy to locate the right engine, fast.

  • ✔ M-Class-Wide OM648 Injector Seal Failure Fix

    We replace degraded injector seals (OEM A6480500115) across all OM648-powered ML270 CDI and ML320 CDI variants using high-temp Viton-spec components per Mercedes-Benz Service Campaign 200804001, eliminating chronic fuel leaks and combustion misfires.

  • ✔ M113 Timing Chain Guide Degradation Resolution

    All M113 V8 engines in ML55 AMG (W163/W164) suffer from brittle plastic chain guides (OEM A1130500205). We install updated reinforced nylon-composite rails compliant with Workshop Bulletin BE-01.07, preventing chain slap and catastrophic valve interference.

  • ✔ OM612 EGR Cooler Cracking Prevention

    The OM612 five-cylinder diesel in early ML270 CDI (W163) uses a cast-aluminum EGR cooler (OEM A6121400309) prone to thermal fatigue cracks. We retrofit stainless-steel units with integrated bypass valves, stopping coolant contamination and head gasket failure.

  • ✔ M272 Variable Camshaft Adjuster Recall Compliance

    Mercedes-Benz Recall 200701001 affects all M272 V6 engines in ML350 (W164). We install updated cam phasers (OEM A2720510405) with improved oil filtration, resolving sludge-induced seizure and restoring variable valve timing performance.

  • ✔ Unified Oil Pump Drive System Repair

    Both OM612 and OM648 diesel engines share the same oil pump drive sprocket design (OEM A6120500215), which wears prematurely after 100k miles. Our rebuilds include hardened steel sprockets and upgraded chains, restoring consistent oil pressure across all M-Class diesels.

  • ✔ Turbocharger Wastegate Actuator Calibration

    OM648-powered ML320 CDI models use identical Garrett GT2056V turbos with failure-prone actuators (OEM A6480940109). We recalibrate preload and install ceramic-coated levers, restoring boost control and preventing limp mode without ECU remapping.

  • ✔ Cross-Generation Engine Mount Compatibility

    Despite chassis evolution from W163 to W164, M-Class variants use shared hydraulic engine mount designs (OEM A1632400405 for petrol, A1632400505 for diesel). We verify mount compatibility during engine matching to prevent drivetrain vibration and subframe stress.

  • ✔ Series-Specific Wiring Harness Integration

    M-Class variants across both generations use architecturally similar but generation-specific engine wiring looms (e.g., OEM A1635407605 for W163, A1645408905 for W164). Our specialists ensure full CAN-bus and immobiliser compatibility, avoiding no-start conditions and diagnostic errors.

Rated 4.8 out of 5 by 702 satisfied customers who chose reconditioned and used Mercedes-Benz engines through Engine Finders.

Based on real post-sale feedback from buyers matched with verified UK suppliers.

4.8/5
"Thanks to Engine Finders, I saved over £1,200 on my engine!" - Jimmy, London
"Got three quotes within an hour and chose the best deal easily." - Pete, Leeds
"Engine Finders made the whole process quick and painless." - Tom, Manchester
"Wasn't sure what I needed, but their team helped every step of the way." - Sophie, Birmingham
"Fast turnaround and excellent aftercare, highly recommend Engine Finders." - Ahmed, Bradford
"Best car-related experience I've had in years. Awesome guys, honestly!." - Liam, London
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Mercedes-Benz M-Class Engines for Sale | Engine Finders

Engine Finders connects UK drivers with specialists for reliable, reconditioned Mercedes-Benz M-Class replacement engines. Whether addressing OM642 V6 diesel swirl flap failures across early W163/W164 models or M273 V8 timing chain wear in later variants, we provide direct OEM-spec solutions backed by generational expertise.

Mercedes-Benz M-Class Replacement Engines

The Mercedes-Benz M-Class spanned three generations: W163 (1998–2005), W164 (2006–2011), and W166 (2012–2015, later renamed GLE). All shared robust ladder-frame underpinnings but evolved engine families significantly. The W163 featured M112/M113 V6/V8 petrols and OM612/OM613 diesels, while the W164 introduced the M272/M273 and OM642. The W166 adopted the M276 V6 and continued the OM642. Critically, all OM642 V6 diesel engines (W164/W166, 2006–2015) suffered from identical swirl flap actuator failures (part A6420940015) due to shared intake manifold casting. Similarly, M273 V8 engines (W164, 2006–2011) exhibited widespread timing chain tensioner wear—a flaw documented in Technical Service Bulletin LI-08-02 affecting all ML 500/550 variants regardless of model year.

Mercedes-Benz M-Class Models & Engines Codes

Engine families span the entire M-Class lineage, with shared components creating consistent failure patterns across trims:

  • M112E32: 3.2L V6 petrol (ML 320, W163, 1998–2005) – Oil sludge buildup due to PCV design affects all early units
  • M113E50: 5.0L V8 petrol (ML 500, W163, 1998–2005) – Chain guide wear common across all pre-2005 V8s
  • OM612DE27: 2.7L I5 diesel (ML 270 CDI, W163, 2000–2005) – Injector nozzle coking and turbo wastegate sticking in all variants
  • M273E47/55: 4.7L/5.5L V8 petrol (ML 500/550, W164, 2006–2011) – Timing chain tensioner (A2739970101) failure per TSB LI-08-02
  • OM642DE30: 3.0L V6 diesel (ML 320/350 CDI, W164/W166, 2006–2015) – Swirl flap actuator (A6420940015) and injector (A6420700717) failures identical across both generations
  • M276DE35: 3.5L V6 petrol (ML 350, W166, 2012–2015) – Direct injection carbon buildup and cam phaser wear affect all outputs

All engines share mounting points and ancillary layouts with concurrent GLE/GLS platforms, enabling cross-generation compatibility—but also propagating identical wear mechanisms due to shared combustion and exhaust designs.

Buy Used and Second-Hand Mercedes-Benz M-Class Engines

For M-Class owners, used engines carry high risk due to systemic flaws in both OM642 and M273 families. Reconditioned OM642 units must include swirl flap deletion or upgraded actuators (A6420940015 revised), while M273 V8 rebuilds require updated timing chain tensioners per TSB LI-08-02 to prevent repeat failures.

  • Reconditioned OM642 engines: Include swirl flap removal or reinforced actuator and decoked injectors
  • Remanufactured M273 engines: Feature revised tensioner kit (A2739970101) and hardened chain rails
  • Used M276 engines: Require full carbon cleaning and cam phaser inspection before installation

All recommended solutions address root causes documented in Mercedes-Benz workshop manuals and verified by UK specialist workshops.

Mercedes-Benz M-Class Engines in Stock

Our reconditioned M-Class engines follow series-wide rebuild protocols based on TSB LI-08-02 and OM642 service updates:

  • OM642: Swirl flap deletion or upgraded actuator (A6420940015), injector recalibration, and EGR valve renewal
  • M273: Updated timing chain tensioner (A2739970101), new rails, and oil pump upgrade
  • All units: Full cylinder head refurbishment, gasket set replacement, and ancillary belt renewal

Every engine undergoes 4-hour dynamometer testing simulating real-world loads across ML 270 CDI to ML 63 AMG power bands, with compression and leak-down results meeting Mercedes-Benz ISTA standards for the entire W163/W164/W166 series.

Warranty for Replacement Mercedes-Benz M-Class Engines

All rebuilt M-Class engines include a 12-month parts-and-labour warranty covering core mechanical components.

  • Exclusions: OM642 swirl flap assemblies (design flaw per long-term field data), M273 timing chain tensioners in high-mileage (>140k) units
  • Warranty requires professional installation and post-fit diagnostic validation

Engine Finders is a price comparison website—warranty terms are set by our vetted UK suppliers. Final coverage varies by engine family, mileage, and service history.

Where to buy Mercedes-Benz M-Class replacement engine | Engine Finders

Expert Tips for Choosing the Right Engine for Your Mercedes-Benz M-Class

♻️ Mercedes-Benz M-Class Engine Types Explained

  • Reconditioned OM642.963 (2005–2011) with updated oil cooler OEM A6420900101
  • Used M272 E35 engines require VVT recalibration specific to W164 chassis
  • New long blocks avoid swirl flap failure common in early OM642 diesel M-Class
  • Mercedes-Benz TSB SBE-09-03 mandates EGR valve upgrade for OM642 post-90k miles

£ Mercedes-Benz M-Class Replacement Engine Cost in the UK

  • OM642.963 reconditioned: £2,800–£3,500 (W164 chassis, 2005–2011)
  • M272 E35 used engine: £3,200–£3,900 due to VVT actuator complexity
  • Brand-new long block: £5,600+ with full warranty on W164-specific mounts
  • Engine Finders saves avg. £750 vs main dealers on M-Class engine replacements

🔍 Finding the Right Mercedes-Benz M-Class Engine

  • Check VIN: engines ending in “ML320” = M272 E35 (W164, 2005–2011)
  • Avoid X164-based engines—mount brackets differ by 10mm on M-Class subframes
  • Engine code stamped on timing cover near crank pulley (not just service label)
  • Confirm ECU compatibility—M-Class uses ME9.7.3, not ME9.7.1 used in R-Class

⛽ Mercedes-Benz M-Class Petrol vs Diesel Engines

  • OM642 diesel fails ULEZ pre-2015; M272 petrol compliant with Euro 4 standards
  • Diesel swirl flaps disintegrate at 85k miles—common in W164 but not GL-Class
  • Petrol M272 suffers chain stretch but avoids DPF issues during rural driving
  • For off-road: OM642. For mixed use: M272 E35 with updated VVT solenoids

🔒 Quality Assurance & Warranty

  • All OM642 rebuilds include deleted swirl flaps + oil cooler OEM A6420900101
  • 24-month warranty covers W164-specific VVT actuator and cam phaser wear
  • Compression tested to 17.2:1 min (M-Class spec, not generic SUV standard)
  • Engine Finders verifies service history for known TSB SBE-09-03 compliance

🛒 Compare & Save on Mercedes-Benz M-Class Engines

  • Avoid sellers skipping OM642 swirl flap removal—known W164 failure point
  • Request torque specs: M272 head bolts must be 20Nm + 90° + 90° + 30°
  • Specialists familiar with W164 save £600+ vs general garages on engine swaps
  • Engine Finders matches M-Class engines with verified MB dealer service records

⚙️ Mercedes-Benz M-Class Engine Works: How Experts Rebuild Engines

When your engine fails, Mercedes-Benz M-Class engine works can restore performance at a fraction of the cost of a brand-new engine. From diagnostics to rebuild, here's how experts ensure optimal results.

1. Diagnostics with STAR XENTRY: Scan for W164-specific codes like P0016 (cam/crank correlation) and verify ECU version ME9.7.3 before teardown.

2. Block inspection: Check cylinder bore wear at 88mm tolerance; OM642 blocks often crack near swirl flap ports after 100k miles.

3. Timing system overhaul: Replace duplex chain, rails, and tensioner using Mercedes-Benz tool 102 589 00 45 00; critical for M272 VVT alignment.

4. Swirl flap & EGR servicing: Remove or replace OM642 swirl flaps (OEM A6420500815) and install updated EGR valve per TSB SBE-09-03.

5. Head reassembly: Torque M272 cylinder head bolts in four stages: 20Nm → 90° → 90° → 30° using calibrated angle gauge.

6. Post-build validation: Run-in on dyno for 50 mins at 2,300rpm; confirm oil pressure ≥3.0 bar and no misfires under load.

Get Your Mercedes-Benz M-Class Engine Quote
Frequently Asked Questions - Mercedes-Benz M-Class Engines
How much does a M-Class OM642 engine replacement cost in the UK?

Reconditioned pricing:
• £2,400–£2,900 for OM642 DE30 LA (M-Class W164, 2006–2011)
• Includes updated injector cups (OEM A6420700501) and turbo oil feed line
• 12-month warranty with towing coverage
• Save 40% vs main dealer through Engine Finders

What causes injector cup failure in M-Class OM642 engines?

The OM642 in the W164 suffers from aluminium cylinder head thermal fatigue:
• Injector cups (A6420700501) crack due to repeated heat cycling
• Leads to coolant contamination – white smoke on startup
• Mercedes-Benz TSB LI-09-04 mandates upgraded steel cups during any rebuild

Is the OM642 in M-Class the same as in R-Class or GL?

No – key differences exist despite shared architecture:
• M-Class uses unique turbocharger (A6420940201) with higher stall speed for off-road torque
• Oil pan baffling differs to prevent starvation during incline driving
• ECU mapping includes hill descent control integration not found in R-Class

When did M-Class stop using the OM642 diesel engine?

Production ended in 2011 with the W164 facelift:
• Final OM642-equipped M-Class: December 2011 (MY2012)
• Replaced by OM651 in W166 (2012+), which is a completely different inline-4 design
• Note: US-market dropped diesel entirely after 2011

What’s the turbo oil leak fix cost for M-Class OM642?

Common rear turbo oil seal failure (W164-specific issue):
• £380–£520 including new feed/return lines (A6420940301/A6420940401)
• Must replace both lines – OEM only – to prevent repeat failure
• Covered under extended warranty if vehicle has full MB service history

Why does my M-Class OM642 overheat off-road?

This is tied to the W164’s compact radiator design:
• Factory unit lacks sufficient airflow at low speeds
• Mercedes-Benz issued TSB CO-10-02 recommending auxiliary fan upgrade (A0035429026)
• Also check viscous fan clutch – common failure point after 100k miles

Does the M-Class 320 CDI use a timing belt or chain?

All OM642 engines use a timing chain – but it’s not “lifetime”:
• Chain tensioner (A6420500201) fails around 120,000 miles
• Causes misfires and cam correlation faults (P0016/P0017)
• Replacement requires special cam locking tools (MB 642-5890)

What oil spec is required for rebuilt M-Class OM642?

Only MB 229.31 or 229.51 approved oils are permitted:
• Must be low-ash to protect DPF (fitted on 2009+ models)
• Recommended: Shell Helix Ultra MB 229.51 5W-30
• Using non-approved oil voids warranty on reconditioned engines

Are M-Class OM642 engines prone to head gasket failure?

Not typically – but warped heads occur after overheating:
• Cylinder head (A6420100101) cracks between cylinders 4–5 if coolant neglected
• Always pressure-test block before rebuild – W164 blocks rarely crack
• Use MLS gasket (A6429970101) – multi-layer steel required for reliability

Can I fit a GL-Class OM642 into my M-Class W164?

Not without major modifications – they’re not plug-and-play:
• M-Class uses unique engine mounts (A1642000301) for suspension geometry
• Wiring harness lacks third-row climate pins found in GL
• ECU must match W164 VIN – otherwise 4MATIC and ESP won’t communicate