The Comprehensive Guide to the Mercedes-Benz M273 Engine
The Mercedes-Benz M273 engine family, introduced in 2005, represents a significant evolution in the brand’s V8 engine technology. Designed as a successor to the M113, the M273 emphasizes performance, refinement, and technological advancements, ensuring that Mercedes-Benz vehicles maintain their reputation for luxury and performance. This guide provides an in-depth look at the M273 engine, its specifications, common issues, and maintenance tips, helping enthusiasts and owners alike navigate the complexities of this remarkable power plant.
Engine Comparison Table
| Engine Type | Displacement | Configuration | Application Models | Notable Features |
|---|---|---|---|---|
| M273 4.7L | 4.7 L | V8 | E-Class, S-Class, G-Class | All-aluminum construction, variable valve timing |
| M273 5.5L | 5.5 L | V8 | S-Class, CLS W218, GL-Class | Forged steel crankshaft, lightweight pistons |
Overview of the M273 Engine
The M273 engine series includes V8 gasoline engines with displacements of 4.7 and 5.5 liters. The design is based on the previous M272 V6 and retains many features from its predecessor, the M113. The M273 was crafted to enhance performance and driving dynamics while emphasizing fuel efficiency and emissions reduction.
Key Specifications
- Displacement Options: 4.7L (M273 46 KE) and 5.5L (M273 55 KE)
- Bore and Stroke:
- 4.7L: 92.9 mm bore, 86.0 mm stroke
- 5.5L: 98.0 mm bore, 90.5 mm stroke
- Construction: Aluminum cylinder block, aluminum alloy cylinder heads, and forged steel crankshaft.
- Valvetrain: DOHC with four valves per cylinder and independent camshaft timing.
Performance and Reliability
The M273 engine family is known for its strong performance characteristics and reliability. The naturally aspirated V8 engines deliver smooth and linear power, ideal for luxury vehicles. While generally robust, the M273 is not without its issues, which can affect long-term performance.
Common Problems
- Intake Manifold Failures: Over time, the intake manifold may develop cracks or leaks, leading to performance issues.
- Camshaft Adjuster Wear: The camshaft adjusters may experience wear, affecting the engine’s timing and efficiency.
- Oil Leaks: As the engine ages, seals and gaskets can degrade, leading to oil leaks and potential engine damage.
Maintenance Tips for the M273 Engine
To keep the M273 engine running smoothly, regular maintenance is crucial. Here are some essential tips:
- Regular Oil Changes: Use high-quality oil and change it according to the manufacturer’s recommendations. This helps maintain engine health and performance.
- Monitor Cooling System: Ensure the cooling system operates effectively. The M273 uses an electronically controlled thermostat for optimal temperature management.
- Inspect for Leaks: Regularly check for any oil or coolant leaks, especially around the intake manifold and camshaft adjuster.
- Fuel System Maintenance: Keep the fuel system clean by using quality fuel and considering periodic fuel injector cleaning.
Technical Features Comparison Table
| Feature | M273 4.7L | M273 5.5L |
|---|---|---|
| Max Power | ~315 hp | ~382 hp |
| Max Torque | ~460 Nm | ~530 Nm |
| Fuel System | Sequential fuel injection | Sequential fuel injection |
| Management System | Bosch ME9 ECU | Bosch ME9 ECU |
| Cooling System | Electronically controlled | Electronically controlled |
| Construction | Aluminum alloy | Aluminum alloy |
Transition to Turbocharged Engines
In 2010, the M273 was succeeded by the M278 engine, which offered turbocharging and greater fuel efficiency. The transition reflects the automotive industry’s shift towards turbocharged engines for enhanced performance and reduced emissions.
Advantages of the M278
- Turbocharged Performance: Increased power and torque across a broader RPM range.
- Improved Fuel Efficiency: Better fuel economy compared to the naturally aspirated M273.
- Lower Emissions: Advanced technology reduces harmful emissions, aligning with modern environmental standards.
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Conclusion
The Mercedes-Benz M273 engine family represents a remarkable blend of performance, luxury, and engineering excellence. While generally reliable, it is important for owners to be aware of common issues and maintenance needs to ensure longevity. Understanding its specifications, problems, and transition to later engine models will equip enthusiasts and owners with the knowledge to appreciate this sophisticated powerplant.
FAQ
What are the main differences between the M273 4.7L and 5.5L engines?
The primary differences lie in their displacement, power output, and torque. The M273 5.5L produces more horsepower and torque compared to the 4.7L version, making it ideal for performance-oriented models.
When was the M273 engine introduced?
The M273 engine was introduced in 2005 as a successor to the M113 engine, focusing on improved performance and technology.
What type of vehicles use the M273 engine?
The M273 engine has been used in several Mercedes-Benz models, including the E-Class, S-Class, G-Class, and GL-Class.
What are common problems associated with the M273 engine?
Common issues include intake manifold failures, camshaft adjuster wear, and oil leaks, which can affect performance and reliability.
How often should I change the oil in an M273 engine?
It’s recommended to change the oil every 7,500 miles or according to the manufacturer’s service schedule, ensuring the use of high-quality oil.
Is the M273 engine reliable?
Generally, the M273 engine is considered reliable, but like any engine, it requires regular maintenance to avoid common issues.
What should I do if I notice an oil leak in my M273 engine?
If you notice an oil leak, it’s advisable to have it inspected by a qualified technician to identify the source and prevent potential engine damage.
How does the M273 compare to the later M278 engine?
The M278 engine features turbocharging, which provides better performance, improved fuel efficiency, and lower emissions compared to the naturally aspirated M273.
Can I use any type of oil in my M273 engine?
No, it’s important to use oil that meets Mercedes-Benz’s specifications for the M273 engine. Always refer to the owner’s manual for recommendations.
What maintenance practices can extend the life of my M273 engine?
Regular oil changes, monitoring the cooling system, inspecting for leaks, and keeping the fuel system clean are essential practices to extend engine life.