Renault Master 2.5 DCI Engine Problems

The Renault Master 2.5dci, especially its 2009 model, is popular for its versatile applications, with many converting it into functional vehicles such as horseboxes. However, like any machine, it is not without its issues. This article sheds light on some of the engine challenges faced by Renault Master 2.5dci owners and potential solutions.

The Problem

One common issue that has come to the forefront is the engine’s problematic behavior after driving. Notably, users have observed:

1. Oil Dispersion: After parking the vehicle, a significant amount of oil is noticed sprayed across the engine. Additionally, the intercooler pipes get filled with oil.
2. Emissions: There’s a heavy emission of white smoke on startup.
3. Self-revving: The engine begins to rev on its own, which can be alarming. This self-revving is not easily controlled by simply turning off the ignition. Some had to stall the vehicle manually to stop the erratic behavior.
4. Turbo Issues: The problems seem to suggest that the turbo might be running on engine oil.

Attempts at Solutions

Several steps were taken by the users to mitigate these issues:

1. Turbo Replacement: Some users have opted to replace the turbo, suspecting it as the root cause of the problem. However, even after this change, the issues persisted.
2. EGR Valve: One user noted that the EGR valve showed a fault. Upon inspection, it was found to be coked up and its flaps seized. Decoking and freeing up the flaps seemed to solve this specific issue.
3. Turbo Oil Feed Pipe: This was also replaced as a potential solution.
4. Intercooler and Radiator: There were suspicions that the engine was pressurizing, which led to oil blowing out of the rocker cover breather. This breather connects to the intercooler pipes just above the turbo.

However, these solutions didn’t seem to eradicate the problem entirely.

Advice and Insights

• Some believe that the replacement turbo was also defective and that this could have further damaged the engine.
• There’s a suggestion that the rocker cover, which also serves as the inlet manifold, might be at fault. Faulty gaskets in this area can cause boost issues leading to oil being pushed out. Replacing the rocker cover might be a solution.
• If oil is present in the intercooler and its pipes, it’s crucial to clean them out thoroughly before any replacements or restarts.
• Another potential area of concern is the engine breathers. If they are not functioning correctly, they could lead to oil being expelled.
• One user noted that if a diesel engine can’t breathe, it can lead to the expulsion of oil.

Conclusion

While there are numerous suggestions and potential solutions, the consensus seems to lean towards severe engine damage, with many advising a complete engine replacement, especially if the vehicle has stopped on its own. Given the complexity of modern engines compared to their predecessors, a professional mechanic’s intervention is highly recommended. Owners should ensure a thorough diagnostic is done before undertaking any major replacements or repairs.