Noisy engine
I have owned the 1994 Mercedesbenz E320 (124) for 18 years and, over time, the area around the front of the engine has been getting very noisy. I want to have the parts around the front of the engine replaced to reduce the noise, which now sound like many worn bearings. I also want to reduce the risk of a sudden component failure and breakdown while abroad. I would like some advice what should be replaced.
The car’s current condition is as follows: 1. For the last 10 years, the car has only done about 3000 miles per annum. It is never used for short journeys, only for long distance driving on the Continent. 2. Regular annual services have been done by a Mercedes specialist, with oil/filter change at least every 3000 miles. 3. The performance of the car is up to spec, with acceleration and top speed almost as per original, although the car is usually driven leisurely at between 6070mph. The engine uses virtually no oil and the car has never broken down. 4. Preventive maintenance has been carried out on the car over the years. Of the parts around the front of the engine, the power steering pump was refurbished in 2002 at 69,000 miles, while the alternator was replaced in 2004 at 85,000 miles. 5. Bodywork is excellent, with no rust on any part, and it’s inspected for corrosion by a specialist every two years. 6. The car is garaged and the battery is on constant trickle charge using a CTEK unit, so that it always starts first go. I am now at an age when I suspect I will not have many more years of driving in front of me. I would prefer to spend some money on getting my car up to scratch, rather than buying a new one. What parts are most likely to be causing the noise and how should I go about identifying them? Should I try listening to the bearings with a long screwdriver? Allan Luskow My first test would be to remove the fanbelt and feel all of the auxiliary pulleys for any wear or roughness in operation. I would then run the engine for a short period of time to check if the noise is still present.
If the noise has disappeared, then you will be looking at one of the external components making the noise. The most likely candidates are the water pump followed by the alternator, but any of the rotating bearings may be the problem. On the other hand, if the noise is still present, the most likely scenario is that the timing chain is to blame, although this would be unusual on a Mercedes engine that has been serviced regularly.