When the Mercedes M271 E18 engine went into production in 2002, it was able to instantly replace every member of the M111 family. A two-shaft balancing system and an entirely new aluminum cylinder block with cast iron liners are used in the new generation of engines.
M102, M111, M133, M139, M166, M200, M254, M260, M264, M266, M270, M271, M274, and M282 are the R4 Mercedes engines.
With two camshafts, four valves per cylinder, hydraulic lifters, and variable valve timing on both shafts, the cylinder head is made of the same material. For the KE (distributed injection) and DE (direct injection) versions of the M271, two types of cylinder heads with distinct intake ducts, combustion chambers, and camshafts were utilized. The intake and exhaust valves have diameters of 30.5 mm and 27 mm, respectively. Additionally, KE and DE have different pistons; the connecting rods come from the M111 EVO.
The supercharger is an Eaton M65 compressor. When the engines were first introduced, the timing drive’s chain could stretch up to 100,000 kilometers; however, this issue was later resolved. Engine management system Siemens SIM4 KE/DE (for M271.942).
The most notable change made to the engine in 2009 was the replacement of the compressor with an IHI Al 0065/0066 turbocharger, which produces 0.5 bar for cars with 156 horsepower and 1.2 bar for those with 204 horsepower. Additionally, the engine management system has been switched to Siemens SIM4 LDE, and the cylinder head has undergone minor modifications. The prefix EVO was added to the name of restyled engines.
Specifications
| Production years | 2002-2015 |
| Displacement, cc | 1796 |
| Fuel system | distributed injection (M 271 E 18 ML) direct injection CGI (M 271 DE 18 ML) direct injection CGI (M 271 DE 18 AL) |
| Power output, hp | 122 – 192 (M 271 E 18 ML) 170 (M 271 DE 18 ML) 156 – 204 (M 271 DE 18 AL) |
| Torque output, Nm | 190 – 260 (M 271 E 18 ML) 250 (M 271 DE 18 ML) 250 – 310 (M 271 DE 18 AL) |
| Cylinder block | aluminum R4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 82 |
| Piston stroke, mm | 85 |
| Compression ratio | 9.0 – 10.2 (M 271 E 18 ML) 10.5 (M 271 DE 18 ML) 9.3 (M 271 DE 18 AL) |
| Features | no |
| Hydraulic lifters | yes |
| Timing drive | chain |
| Phase regulator | on both shafts |
| Turbocharging | compressor (M 271 E 18 ML) compressor (M 271 DE 18 ML) IHI Al 0065/0066 (M 271 DE 18 AL) |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 5.5 |
| Fuel type | petrol |
| Euro standards | EURO 4/5 |
| Fuel consumption, L/100 km (for C200 Kompressor W204) — city — highway — combined |
9.5 5.5 6.9 |
| Engine lifespan, km | ~320 000 |
| Weight, kg | 160 |
Disadvantages of the M271 E18 engine
Soot-related stuck exhaust valves are the most well-known engine issue.
The unreliable timing chain, which has a maximum length of 100,000 kilometers, comes in second.
Frequent lubricant leaks from the heat exchanger or oil filter housing follow this.
The crankcase ventilation system soon gets so filthy that the tubes burst.
Fuel seeping into the oil is a proprietary issue with the EVO series engines.