What Causes Bent Valves? (Top 6 Possible Causes)

Causes of Bent Valves

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No component of a vehicle would bend if there’s no serious force acting on it. For the valves to bend, definitely, a superior force acted on them. Valves play an important role in controlling air intake and combustion emissions removed from the engine. When the valves are bent, the engine will malfunction or break down.

But what causes bent valves? There are pretty many reasons why a valve would bend, this includes excessive overheating, over-revving, poor lubrication, etc.

It is important that you replace bent valves as soon as possible to avoid further damage to your engine. Interestingly, this article explains the various causes of bent valves and how you can fix them.

What Causes Bent Valves?

What Causes Bent Valves

There are several reasons why valves bend; however, hereunder are the commonest reasons why it happens.

1. Low Oil

Poor lubrication is one of the major causes of engine failure. Every part of an engine needs to be constantly oiled to run smoothly with less or no friction. When oil is not properly saturated inside an engine, it increases friction, which in turn causes wear.

Low oil in the engine can cause the valve to get stuck in the valve guide, which can cause it to get bent, over time. Thus, it is advisable to keep your engine’s oil level in check and don’t skip your oil change intervals.

2. Engine Over-Revving

Every engine has a maximal limit it can handle several operations. Similarly, every engine has a maximum number of RPM it can operate with.

Now, if you constantly push the engine to function above its maximal RPM, that could cause serious damage to the engine components, which also includes causing the valves to bend.

Related Post: Will a Car Run With Bent Valves?

3. Unprofessional Engine Rebuild

Most drivers opt-in for engine rebuilds when they feel like the stock engine on their cars is no longer as efficient as it used to.

Engine rebuilds can make an old car drive and sound like a new one if done properly. In contrast, when it’s not done properly, it can lead to the damaging of certain internal engine components over time.

4. Broken Timing Belt

Another common cause of bent valves is when your engine’s timing belt is broken. A damaged timing belt can cause many things to go bad inside the engine; this mostly applies to cars with interference engines. Cars with interference engines have close tolerances between valves and pistons.

Hence, when the belt is bad, the engine is most likely to keep turning until the pistons and valves come in contact. This action can cause the valves to bend or affect the pistons. In worse scenarios, a broken timing belt may also damage the engine heads.

5. Incorrect or Improper Valve Lash

If the valve lash clearance is not properly set, it can lead to damage to the valve and other related components.

When a valve’s lash clearance is too tight, it can cause the valve not to close properly, thus, causing excessive overheating, and possibly, complete valve failure.

6. Improper Maintenance

There is no doubt that improper maintenance can make an engine go bad, or even break down earlier than expected.

Maintaining your engine includes using the recommended motor oil, going for servicing regularly, and replacing your oil when due. Also, you should always check your car from time to time and fix minor issues earlier.

Read Also: What Causes a Crankshaft Seal to Leak?

Conclusion | Causes of Bent Valves

Listed above are the most common reasons why valves bend. When a valve is bad, you’d typically notice that your engine overheats and uses more fuel and oil than it ever did.

While other issues could trigger these symptoms, a faulty or bent valve is one of those issues.

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