Symptoms of a Failing Mercedes Timing Chain

When your car begins to make odd sounds or you can tell something is wrong, it can be tricky to narrow down the culprit. Is there a problem inside the engine? Is it a simple matter of low oil? Is it time for a tune-up? There can be a variety of causes for car trouble, but we developed a guide to help you investigate a timing chain problem.

At Burdi Motorworks, we have the experience and knowledge to determine if your Mercedes-Benz has a bad timing chain, taking the guesswork out of the equation. Call our mercedes repair shop near Chicago, IL for an estimate.

What Is a Timing Chain?

A timing chain is an integral component of an engine, and without it, your Mercedes would be useless. In general, it comes down to the mechanics of engine timing. Most cars have a four-stroke motor with a combustion process that includes an intake, exhaust, compression, and power stroke system. Within the four-stroke arrangement, the camshaft spins once while the crankshaft rotates twice. The relationship between the two is mechanical timing, which controls the engine's pistons and valves.

As for the timing chain, it allows the camshaft, balance shaft, and crankshaft to rotate in synchronization. The crankshaft controls the position of the pistons, causing the shaft to rotate, while the camshaft controls the intake and exhaust valves.

The valves allow air and fuel into the engine and help emit exhausts at the same time. Timing chains, therefore, control the drive of the camshaft and maintain the precise timing of the valves. They keep the bottom engine components in synchronization with those in the top half.

A timing chain contains a series of links, similar to a bicycle chain. The links run on toothed sprockets (gears) that are on the ends of the crankshaft, camshafts, and additionally the balance shaft. After several thousand miles it is not uncommon for a timing chain to stretch. This can cause a check engine light to appear, poor engine performance, or an unusual sound coming from your engine.

Then, a timing chain tensioner does as you may think — keeps the chain under the correct tension. Generally a spring loaded mechanism operates the tensioner. And to keep the engine timing chain from vibrating, rails, and chain guides help keep it quiet.

How a Mercedes timing chain works relates to the performance level of the motor. Most higher-displacement engines have a timing chain. The chain, mostly located in front of the motor, attaches to gears and pulleys that power several mechanical components. It must rotate around the gears of the crankshaft and camshaft without restriction to start the vehicle. To create a smooth start, the chain requires proper lubrication from the engine oil. That is why it is very important to always perform service on time. Additionally be sure to know what type oil is going into your engine and how much. Too many oil lube express facilities use low cost engine oil, economy oil filters, and sometimes do not add the correct amount when changing engine oil. Mix that with a few times going over the mileage due and you have made a perfect environment for a timing chain failure.

Common Problems With Timing Chains

Like all vehicle components, timing chains are subject to typical wear and tear. The metal “stretches” over time, which causes inaccurate timing of the crankshaft, and the camshaft will lag. Problems with the timing chain cause weak fuel economy and lower engine performance.

A loose chain will look more elongated and will form a bubble-like motion around the sprockets — also known as slack. The metal links don't really stretch, although it seems like it. As tension decreases, slack in the chain causes it to loop out at one end instead of creating a consistent movement. The links move further apart, as opposed to stretching in length.

If you need a Mercedes timing chain repair, there could also be low oil levels in the motor. Other factors that can affect the timing chain performance are irregular oil changes and poor oil quality. Even working with the wrong oil type can cause problems.

Then there are interference vs. non-interference motors that affect timing chain complications. An interference engine is where the cylinder contains the pistons and valves, but not simultaneously. A broken chain in this instance can result in the parts flying into the cylinder, causing severe internal damage.

However, it wouldn't happen with a non-interference engine because the pistons and valves aren't in the same area. A non-interference engine provides adequate clearance to prevent the valves from hitting the pistons.

Chain complications will cause the links to often loosen before breaking, and breakage can occur while driving or turning your car on and off. If it disrupts at a low speed, it may result in little damage. But running at high RPMs can destroy your Mercedes engine.


When Should You Replace a Timing Chain?

When to change a Mercedes timing chain is at the first sign of engine chain problems. It's imperative to act right away and contact the experts when you become aware of any failing symptoms. If you hear, experience or see complications, waiting to make a replacement will cause severe damage to your car's engine. Trusting Burdi Motorworks to make repairs before further damage occurs can increase the longevity of your vehicle.

You can also reduce the probability of timing chain failures by performing regular maintenance and referring to professional mechanics for inspections. Always be proactive and alert for symptoms because it can extend the life of the engine and save you money in the long run.

Manufacturers don't often place an upper limit on the longevity of a chain. They deem it to last the lifetime of your engine, which depends on various circumstances like how you drive, how far, etc. However, in higher-mileage Mercedes vehicles, the timing chain can start to wear faster, creating problems that lead to engine failure. While Mercedes timing chain replacement is rare, take swift action whenever issues arise.

Symptoms of a Failing Mercedes TimingChain

Timing chain symptoms are pretty obvious, ranging from rattling sounds and engine misfires to engine failure and the use of improper oil. The simple guide will help you be aware of timing chain failure in your Mercedes.

1. Rattling Sounds While the Vehicle's in Idle

Timing chain noises are one of the most obvious indications of a failing component. Unusual engine sounds and motor vibrations are a warning sign that can relay the problem of a loose timing chain. A consistent, smooth sound will indicate normal conditions and that everything is running as expected. On the other hand, if you hear a rattling noise, it means a part is loose inside the engine.

Slack in the chain permits the metal to hit the timing cover, which can produce debris and wear out the chain. The constant connection can even form a hole in the cover, causing an oil leak. If you hear a noise and then it stops, don't mistake it for the problem going away. Internal engine damage can be a result of the loose and rubbing chain.

2. A Misfiring Engine

The timing chain method to achieve valve timing is the most typical among consumer vehicles and other high-performance cars. Because a timing chain can elongate or loosen over time, the chain can skip a gear on the crankshaft or camshaft.

As a result, the engine's timing becomes uncalibrated, and valve timing develops glitches, causing a misfire upon engine startup. The motor may also lack accelerating power. If the timing chain breaks, metal pieces can roll into the engine, leading to severe damage.

3. Metal Shavings in the Oil

Over time, oil separates from the heating of the motor and from being exposed to the natural solvents in gas. A worn-out timing chain can leave small, broken pieces in the oil pan, which you may notice when draining your Mercedes' oil.

If metal shavings drip out, it can be an indication of a failing timing chain. Metal shavings are also an excellent warning of worn-out keepers, cylinder head valves, retainers and other hardware. You should change your oil and filter about every 5,000 to 7,500 miles to avoid internal engine failures.

4. Engine Fails to Start

A broken timing chain will cause engine failure because the motor won't have suitable compression to start up. If your chain breaks while driving, the pistons will become impaired because of contact with the valves. The valves can even bend and ruin the engine. As the timing chain jumps, meaning it skips links, the loose components can move around and damage other engine parts, resulting in power loss.

5. Check Engine Light Is On

The check engine light in your Mercedes can indicate many problems, including a failed timing chain. The light comes on when there are problems with engine operations or the emissions system. Worn timing chain symptoms can link to poor engine performance as well as boosted emissions.

6. Improper Oil Filter

Oil pressure from the car operates most timing chain tensioners. As the motor starts up, oil pressure helps the tensioner push the guide against the chain, removing slack. Turning off the car allows the oil pressure to return to zero.

No oil pressure means gravity pushes the oil into the upper portion of the engine, back into the oil pan, leaving the oil flow passages empty. In exchange, it increases the time it takes to return the oil to the tensioner when starting the engine again.

An anti-drain-back valve keeps oil in the passages that lead to the hydraulic tensioner, blocking the return of the oil through the filter to the oil pan. If there is no oil in the passage, it means it takes longer for the oil pump to pressurize the tensioner.

A lack of tension creates slack in the timing chain, causing it to jerk on startup, increasing wear and tear. Jumping can even break the chain guides, meaning the camshaft timing will be off and engine performance will decline. All in all, you need a proper oil filter and valve system.

7. Using the Wrong Oil

Timing chain problems can be a product of improper oil specifications and viscosity. A low-viscosity oil encourages faster flow compared to a heavier option. Engines with timing chains specify quick-flowing oil to pressurize the tensioner, keeping the chain tight to reduce breakage. The chain also requires suitable lubrication, so make sure you're using the oil that matches your Mercedes' requirements.

Hearing a harsh noise on startup, worn or discolored chain guides, squealing tensioners and a rough-running engine are all signs of needing a timing chain replacement.

All the symptoms listed above point to a worn timing chain. Our technicians will recognize faulty sounds, oil contamination and others right away. If you continue to drive your vehicle with a worn timing chain, it can lead to further damage, so schedule a service appointment as soon as possible.

What You Can Check to Resolve Chain Problems Before Breakage

While timing chains last longer than belts and are more reliable, constant wear and tear can lead to impairment. The first thing you can do is to always be aware of strange rattling sounds. Others include the following.

  1. Check motor oil levels: If there is a low oil level, the oil pump will ingest an excessive amount of air, triggering the timing chain adjuster not to have proper tension on the chain. Also, check for oil sludge under the camshaft cover. Is the oil of the right viscosity and specification? Are you using OEM oil filters?
  2. Manual vs. automatic Mercedes: Manual transmissions are more susceptible to jumping a timing chain tooth. If you press the clutch in, turn off the engine and use the first gear as a parking brake, the vehicle may roll backward when the clutch releases. In turn, it causes the crankshaft to move back, making one or more timing gear links jump.
  3. Conduct a timing test: At Burdi Motorworks we are able to manually check to see if your engine is in perfect timing. With the use of our Mercedes Benz diagnostic equipment and knowledge we can properly diagnose to see whether or not your in need of a timing chain replacement.

Mercedes Timing Chain Recall Information

If you're searching for recall information, refer to your local Mercedes repair shop for more details. You can also visit the Mercedes Benz VIN Lookup Recall Information Tool to see if your vehicle is applicable for recalls. Enter your vehicle ID number and receive up-to-date info about previous and current recalls. It works only for U.S.-based numbers and is Mercedes' way of providing exceptional customer service to drivers like you.

Mercedes Timing Chain Repair and Replacement Services in Chicago, IL

As an independent Mercedes repair facility, Burdi Motorworks offers competitive pricing on all our parts, services and accessories. Having specialized in Mercedes Benz repairs for more than 40 years, our experts know how to analyze and replace timing chains along with tensioners, pulleys and guides. Our services are less expensive than dealerships and other alternative repair shops.

We are a family-owned and-operated business that delivers the highest value for your needs. Dedicated to top workmanship, value and convenience, Burdi Motorworks creates a relationship with you to ensure efficient and proper maintenance.

Visit our new modern facility in Schiller Park near O'Hare Airport. Our operations include the tools and experience necessary to repair your timing chain guides, tensioners or your timing chain itself to get your Benz back on the road faster and safer.

Schedule a Mercedes timing chain replacement in Chicago or give us a call to speak with a technician. We uphold a reputation as a leader in Mercedes-Benz and Sprinter maintenance, service and repair in the Chicago area.