Timing chain for different automobiles
Engine oil (motor oil)(1851 items)
Water pump + timing belt kit(6167 items)
Engine mount(30947 items)
Valve gasket (rocker cover gasket)(11785 items)
Oil drain plug(1672 items)
Your Timing chain worn out? » Read more about common malfunctions • Repair • Replacement manual
Reliable valve clearance thanks to the timing chain
The timing chain is a very durable and reliable construction for controlling the engine. It is usually much more durable than the alternative: the widespread timing belt. Timing chains are typically installed in premium vehicles. Nonetheless, upon reaching a higher mileage, replacement of a timing chain might become necessary. Although this task is challenging, with some practice it can also be mastered by a talented amateur mechanic.
Sensitive engine control
For an engine to work in the first place, up and down movements of the pistons must be accurately clocked with the opening and closing of the valves. Naturally, the moment of fuel injection and the ignition of the spark plug must also perfectly match to ensure correct engine operation. Yet, when it comes to valve control, accurate clocking is particularly important from a constructive point of view: On most vehicle, piston stroke and valve travel intersect in most vehicles. Once the piston rises for compression or to emit exhaust gas, no valve may be in the way anymore. If the piston hits the valve, typically the exhaust valve, it will usually destroy both, the piston and the valve. Repairing this type of damage is very complex and an economic total loss in most vehicles.
Function and location of the timing chain
The valve control's chain connects the crankshaft to the camshaft. The crankshaft raises and lowers the pistons, while the camshaft opens and closes to the valves. The timing chain synchronizes these movements with each other in such a way, that the engine runs optimally and damage is avoided. The valve control's chain must be kept under tension. This is ensured by a timing chain tensioner. Usually, this is a sliding rail, which is pressed against the chain strand by means of a thread adjustment. With age, the timing chain tensioner can wear, especially given inadequate lubrication.
Timing chain defects
The valve control's chain can fail for three reasons: Wear, stretching or tearing. The most common case is stretching of the chain. This occurs when the timing chain tensioner was applied too tightly. After a certain mileage, upwards of 150,000 km on most vehicles, the chain may simply reach the end of its service life absent of any exterior factors.
Modern vehicles feature self-diagnostics for detecting timing chain wear. It displays a warning or an error message when the chain needs to be replaced. Other symptoms include poor cold start behavior, an unusual pinging and rattling engine noise and rough idling. Oftentimes the atypical noise is misdiagnosed as a transmission defect. The distinction is quite simple: If the noise occurs, even if the car is standing still and the transmission is disengaged, it can't come from the transmission. If it only occurs while driving, the "transmission defect" diagnosis is more likely to be correct. The maintenance manual also prescribes the replacement of the timing chain. However, experience has shown that replacement of the timing chain is indicated much sooner, especially in younger vehicles. Some vehicles of the Mercedes CLS series are particularly well-known for such issues. There are cases, in which the timing chain on these cars needed to be replaced after only 60,000 km. Replacing the control chains Replacing a valve control chain takes about 6 hours, if performed by a specialized workshop. This goes to show how enormously complex this task is. As a motivated and talented hobby mechanic, you should reserve an entire weekend for this job. Replacing the valve control involves exposing the entire chain drive. Next, crankshaft and camshaft must be locked with a special tool. The necessary special tool costs approx. 80-120 euro. After that, the impellers and the chain can be removed. As a rule, the timing chain tensioner is also to be replaced. The same applies to all other slide rails. Timing chains are generally sold in complete sets including all seals. If this set also contains the drive wheels, it is strongly recommended to replace them, too.
Due to the large number of moving parts, using the correct oil is essential to a chain-based valve control. Quality chain by a brand manufacturer A complete repair kit for a chain-based valve control by the brand manufacturer FEBI BILSTEIN costs about 120-180 euro. Due to the importance of this component and the dire consequences of its failure, customers should only put their trust in brand quality.