Con rod bearing failure is a critical automotive issue that, if not promptly addressed, can cause significant damage. In this post from Arsintrading, we will explore the reasons behind con rod bearing failure in Kia vehicles and what causes this issue. Sometimes, the damage is so severe that the engine fails and won’t restart. In such cases, the engine must be fully disassembled and rebuilt.
In December 2020, Kia Motors recalled 295,000 vehicles due to con rod bearing failure. These vehicles included models from 2011 to 2013, such as the 2012 to 2013 model year Sorento, 2012 Sportage, 2012 to 2015 Forte and Forte Koup, 2011 to 2013 Optima Hybrid, and 2014 to 2015 Soul. All these models faced issues related to con rod bearing failure.
Bearing failure in these vehicles could lead to hazardous problems such as puncturing the engine block, which causes severe disruptions in the vehicle’s operation. The main question is, what is con rod bearing failure in Kia vehicles, and how can it be prevented? We will address these points in the following sections.
What is a Con Rod Bearing?
Various bearings are used in automobiles, including some crucial ones in the engine. One of the essential bearings in a car is the engine bearing, situated between the connecting rod (conrod) and the crankshaft. The con rod bearing prevents direct contact between the con rod and the crankshaft, reducing friction.
In vehicles, bearings and engine oil work together to minimize friction between engine components and prevent wear due to direct contact. Bearings avoid friction between the crankshaft and the cylinder and between the crankshaft and the connecting rod.
When the temperature of the bearings exceeds their capacity, and they deform from their original shape, they can no longer perform their function, leading to what is known as con rod bearing failure.
Understanding the causes and symptoms of con rod bearing failure in Kia vehicles is crucial. Remember, a lack of awareness about this condition and continuing to drive and exert pressure on the engine can lead to engine failure and significant repair costs. Can a car with con rod bearing failure still start?
The Role of Con Rod Bearings in a Car
- Regulating Vertical Clearance: Ensuring proper vertical clearance between the cylinder and crankshaft.
- Reducing Friction: Minimizing and virtually eliminating friction between the cylinder and crankshaft to an acceptable level.
- Preventing Wear: Reducing friction between the connecting rod (conrod) and crankshaft to prevent their wear.
When this component overheats for any reason, it deforms, and if it melts, it causes the con rod to stick to the crankshaft, potentially leading to engine failure.
What Does Con Rod Bearing Failure Mean?
Con rod bearing failure occurs when the bearing itself becomes problematic. A loud noise is typically heard when a car experiences con rod bearing failure, and the vehicle requires significant force to start (due to high engine friction). If the engine isn’t turned off immediately, it could suffer severe damage.
What Causes Con Rod Bearing Failure in a Car?
Any factor that deforms or damages the bearings to the point where the bearing either sticks to the crankshaft or creates excessive clearance will prevent the oil film from adequately filling the gap. This condition is referred to as con rod bearing failure.
When the bearing contacts and sticks to the crankshaft, the engine’s movement (crankshaft rotation) becomes heavy, eventually leading to engine failure. If the bearings lose their standard thickness due to wear, the crankshaft can no longer operate smoothly, as its standard clearance is compromised. During operation, a knocking sound will be heard from the area of the faulty bearing.
Symptoms of Con Rod Bearing Failure in Kia Engines
Upon noticing any of the following symptoms in your vehicle, immediately turn off the car and have it towed to a repair shop. Many drivers have ignored these signs, leading to significant damage. Here are the primary symptoms of con rod bearing failure; remember them well:
- Knocking Sounds: A “knock-knock” or “tick-tick” noise from the engine when accelerating.
- Engine Lock-Up: The engine seizes and cannot be started.
Engine Lock-Up and Failure to Start
An engine lock-up occurs when the engine cannot start at all. If the engine doesn’t start despite cranking, one possible reason could be con rod bearing failure.
Understanding and recognizing these symptoms early can prevent further damage and costly repairs. By being aware of the causes and signs of con rod bearing failure, you can ensure timely intervention and maintain the health of your vehicle’s engine.
Knocking Noise from the Engine When Accelerating
If you hear a knocking sound from the engine when accelerating and increasing the RPM, it’s likely a sign of con rod bearing failure. In this situation, it is advised to stop the vehicle immediately and call for a mechanic. If that’s impossible, transport your car to the nearest authorized and reputable repair shop without starting the engine.
At idle speed (around 970 RPM), you might not hear any unusual sounds from the engine. However, as the RPM increases beyond 1200, the sound of the moving bearings becomes quite noticeable. This noise is similar to the sound of two metals striking each other and is often described as a “knock-knock” sound.
Ignoring such noises can lead to substantial repair costs and more severe problems.
Oil Check Light Illumination
While the illumination of the oil check light is not always directly linked to con rod bearing failure, it is a potential indicator. If this light turns on, investigate the issue promptly to rule out bearing problems.
Reduced Engine Power
If your vehicle feels underpowered, struggles to accelerate correctly, or doesn’t respond as it should, it may be a sign of con rod bearing issues.
Remember, each of these symptoms could stem from various other causes. However, if you notice any of them, either individually or together, it is crucial to have your vehicle checked by a professional mechanic.
Driving under these conditions can exacerbate the problem, potentially leading to irreparable damage to components like the crankshaft or bearings, which could require replacement rather than repair.
Causes of Con Rod Bearing Failure in Kia Engines
Any factor that prevents sufficient oil flow to the bearings can lead to con rod bearing failure. Key causes include:
- Faulty Oil Pump: An oil pump that isn’t working correctly can’t supply enough oil to the bearings.
- Overheating: Overheating due to lack of coolant (from leaks in the radiator, hoses, or other sources) can cause the engine to overheat, similar to how fever can lead to convulsions in the human body.
- Dirty Oil and Filters: Filthy and clogged filters can prevent proper lubrication.
- High Engine Speeds: Running the engine at very high speeds can push it into the redline range, causing extreme wear.
- Low-Quality Engine Oil: Using inferior or fake engine oil and delaying oil changes can lead to sludge formation. This sludge can block oil passages and impede the proper lubrication of bearings, putting them under severe stress.
Poor Quality Engine Oil
Using poor quality, non-genuine (fake) oil and delaying oil changes can cause the oil to become sludge-like. This sludge can form deposits that clog the oil passages and pump, preventing the proper lubrication of the con rod bearings and leading to severe wear.
Overheating Engine
One of the primary reasons for con rod bearing failure is engine overheating. This can be caused by several factors, including running the engine without enough coolant. This overheating can deform the bearings, leading to failure.
Understanding and addressing these causes promptly can help prevent con rod bearing failure and maintain the health of your vehicle’s engine.
Contamination in Bearings
Foreign particles that settle on the bearing surfaces can cause premature wear. Abrasive particles accelerate bearing damage, roughen surfaces, and slow the bearing’s operation. Excessive wear results in excessive clearance within the bearing.
Wear and Aging of Components
In addition to contamination, the wear and aging of bearings can lead to their failure or breakdown. Over time, bearings may deteriorate and fail to function correctly, leading to the issues we are concerned about.
Oil Pump Failure
A malfunctioning oil pump can disrupt lubrication, increasing the risk of bearing failure. Similarly, a dirty oil filter can have a similar negative effect on lubrication and bearing health.
Improper Driving
Improper driving is a common but often overlooked cause of bearing wear and damage. Proper driving means avoiding running the engine at the line or near it. If you frequently press the accelerator hard enough to push the engine close to the redline, you put the bearings at risk of damage, stress, and premature wear.
Bearing Corrosion
Corrosion in rolling bearings can occur in various forms and for different reasons. Corrosion damage is often noticeable by the noise the bearing makes during operation. Rust from corrosion causes the bearing surfaces to wear out, leading to significant damage.
Preventing Con Rod Bearing Failure
To prevent con rod bearing failure, follow these fundamental practices:
– Regular Oil Changes: Perform oil changes on schedule to ensure proper lubrication.
– Timely Vehicle Check-ups: Follow scheduled maintenance to catch potential issues early.
– Inspect for Leaks: Regularly check for leaks in the radiator, oil pump, and lubrication system. Any leaks or faults in these components can increase the risk of bearing failure.
By adhering to these maintenance practices and addressing any issues promptly, you can minimize the risk of con rod bearing failure and ensure the longevity of your vehicle’s engine.
