What Causes Burnt Valve? All you Need to Know
A common problem that many drivers face with their car engines is burnt valves. The issue arises when the part that seals the cylinder head gets scorched. It’s best to address the problem immediately to avoid damage to its adjoining components.
Typically, an engine’s valve gets burnt for the following reasons;
- Engine misfiring
- Wrong amount of gap in the spark plug
- Disproportional fuel and air mixture
- Defective exhaust valves
Our article will explain the reasons for what causes a burnt valve.
Causes of Burnt Valves
Below are the most prominent reasons why a valve gets burnt. Continue reading for the in-depth explanation.
1. Overheating
Driving your car for a long time or excessively can cause its interior to experience high temperatures.
Once the heat levels exceed their tolerance, the valves can’t seal properly due to damage to its body. Thus, gaps form between it and the combustion chamber.
Burns to the valve usually occur due to a lack of care or maintenance. Failing to conduct routine maintenance deprives the component of timely upkeep.
Thus, it becomes weak and prone to damage due to high temperatures.
2. Disproportional Spark Plug
Each car model requires a specific spark plug gap to function correctly. Often, a miscalculation in space occurs, resulting in burnt valves. If it’s more than the recommended amount, the cylinder will take excessive oxygen.
Pre-ignition chances increase dangerously if the spark plug gap is too large. It causes the piston to move at a faster rate.
Due to the abnormality, the combustion chamber overheats and causes the valves to get burnt.
3. Wrong Oil and Oxygen Combination
Too much or too little air entering the engine can mess up the car’s oxygen and oil mix, which is necessary to perform effectively. It causes excessive heat and damages the other components of the vehicle.
If such a problem occurs, then it’s vital that you thoroughly inspect the engine management system.
Among the many flaws that may pop up, the chance of discovering burnt valves is a possibility.
4. False Cam Timing
Correct positioning of the crankshaft and camshaft is necessary for both components to work properly.
Sometimes, they don’t align properly. Their misalignment results in friction between the two components, which increases the interior temperature.
Therefore, it’s entirely possible that the excessive heat from the friction of these two parts can burn the valves.
Conducting routine surveillance is necessary to ensure that the timing belt is properly in place to avoid this problem.
5. Low-Quality Valve
Sometimes, drivers tend to purchase aftermarket valves to save costs. However, these products do not have the same durability or finish as their stock counterparts.
Therefore, they tend to wear out faster and become rigid over time.
Excessive heat enters the cylinder when the defective valves start to malfunction. In this scenario, it’s necessary to replace the valves immediately.
Otherwise, they can end up burning as well as harming other parts of the car.
Symptoms of a Burnt Valve
There are actually multiple telltale signs that your car has a burnt valve. Keep on reading to identify them for a fast diagnosis.
1. Power Failure
A clear indicator of burnt valves is the uneven power distribution of the car. It’s easily noticeable when driving up a slope or during acceleration.
Power failure is also apparent when the vehicle struggles to gain accelerate at a consistent rate.
You need to know about your car’s RPM range to notice power failure. If the energy production is uneven within the model’s bracket, then it’s possible that it has a burnt valve.
2. Abnormal Smoke Emission
Car backfiring is a common trait in old cars, which causes a lot of smoke to come out. It’s a sign that many of its components are either old or worn out. Burnt valves are also a possible reason behind this issue arising.
An easy way to understand if burnt valves are the reason behind the excessive smoke is by checking their quality.
If the gas’s color is white or gray and has a horrible odor, it’s a clear indicator that the valves are scorched.
3. Fuel Economy Deterioration
Mileage is a vital feature in cars. Understanding how much distance the car can cover on one gallon of fuel is necessary. Drivers rely on this feature to plan the car’s monthly gasoline budget and the gas stations to hit during road trips.
If the car’s fuel economy is lower than normal, it’s a possible sign that it has burnt valves. The poor condition of the component causes it to consume more fuel than usual. You may also experience leakages if you do not get a replacement soon.
4. Check Engine Light Activation
The “check engine” light usually turns on whenever there’s an issue with the system or any of its components. Since the valves are also a part of the module, then the signal will activate if it’s burnt.
5. Unnatural Noises
A deficiency of the valve will also impact the engine. Since both parts are connected, inefficiency or damage on one of them will also harm the other one. A common scenario, in this case, is unnatural noises coming from the car’s interior.
Knocking noises due to acceleration are a common sign of burnt valves. The air starts to come out of the valve due to its scorched body.
As a result, the combustion air begins to fill with abnormal pressure. Thus, the sound starts to happen whenever the piston crosses it.
FAQs
a. Can a burnt valve affect the car’s oil consumption?
A burnt valve tends to consume more oil than usual. Furthermore, they also tend to burn fuel in some instances.
b. What is a valve seal?
Valve seals are part of engine valves that prevent the motor oil from entering the combustion chamber.
c. When should car valves be replaced?
It’s best to replace them within 3-5 years to stay on the safe side.
Conclusion
Burnt valves are a major problem in cars which can harm its other parts if left unchecked. Conducting routine maintenance can easily help you remain aware of its condition and take necessary precautions before the situation worsens.
Although various factors can contribute to valve burning, it’s crucial to remember that the main cause is overheating.
Therefore, it’s vital that the car’s temperature remains at the recommended level to prevent this problem from arising.
