Part I – Mercedes Benz c-class timing chain (W203-W204) C180/C200/C250Timing Chain & Cam Adjuster Issues
Unfortunately we are seeing a common fault amongst the Mercedes-Benz W204 body C200 & C250 engines more often than we’d like to. Being Mercedes-Benz owners and fans ourselves, we hate seeing these beautiful cars having such a major issue.
The problem mainly affects the later version of the M271 variants of these engines fitted to these vehicles, which is the ‘M271.8 – CGi’ (turbo) that is found in W204 body Mercedes-Benz. Though we have seen similar issues in it’s older version ‘M271.9 – Kompressor’ (Supercharged), in which camshaft adjuster teeth wear away and cause damage to the timing components. The earlier Kompressor variant of the M271 was also found in the earlier W203 bodied C180 and C200.
Because this fault has to do with the timing of the engine, it can definitely cause complete engine failure due to possible valve contact with piston which in-turn means an engine replacement is required. So with that being said, it is definitely something that should be repaired ASAP.
What parts are affected and require replacement?
The main cause of this fault, we believe, is a design fault in the camshaft adjusters that once worn, fail to correctly time the engine and can cause the timing chain to stretch to the point that it breaks completely.
The cam adjusters are located on the front end of each camshaft and are controlled by oil pressure delivered via a solenoid. The adjusters have a spring inside that allows them to use the oil pressure to advance or retard the timing. Once the adjuster fails internally, the internal spring is not able to correctly maintain constant pressure against the camshaft, causing the adjuster to ‘slap’ back and forth creating the loud rattle. These varying pressures on the chain links from the teeth on the adjuster is what causes the stretching of the chain.
Depending on how severe the fault is, the following parts are usually replaced during the repair:
- Intake and/or exhaust camshaft adjuster
- Timing Chain
- Timing Chain Tensioner
- Sealant (Renewed on all removed timing covers)
- Oil & Oil Filter
After the parts are replaced and engine is running, we then clear all the fault codes in the ECU and reset adaptive values. This means the ECU can recognise the new chain is installed.
How will I know if my car has this issue?
There are a few signs to look out for:
- Loud rattle during cold start or while idling.
- Possible loss of power.
- Engine cranks longer than normal before starting.
- And, most likely will have an engine light on.
What should I do if these signs are evident?
If you experience any of the symptoms listed above, have your car checked ASAP. Call and let us know you have read this blog and let us know what symptoms you have found and we’ll book you in to have your car checked out, free of charge, as soon as possible. Using the Mercedes-Benz scan tool, we will be able to find out exactly what has failed and we’ll then let you know exactly what needs to be replaced and give you a quote.
With much experience in carrying out these repairs, and having all the special tools required to complete the repair, we are able to get the job done accurately and quickly, saving you lots on labour charges. Our prices are extremely competitive and our technicians are fully qualified and highly skilled with Mercedes-Benz vehicles.
If you would like more information on this, or any other fault you may have, please feel free to call us.
C&S Service Centre – Ph: 9484 6806