1. Coolant Contamination: Antifreeze is primarily composed of ethylene glycol, which is harmful to engine components when mixed with oil. When antifreeze enters the oil pan, it dilutes the oil's lubricating properties, reducing its effectiveness in providing a protective film between moving engine parts.
2. Loss of Lubrication: As the antifreeze mixes with the oil, it reduces the oil's viscosity, making it thinner and less capable of providing adequate lubrication. The reduced oil viscosity leads to insufficient oil pressure, preventing sufficient oil from reaching the rod bearings.
3. Heat Buildup: The reduced oil flow due to antifreeze contamination causes increased friction between the rod bearings and the crankshaft journals. This increased friction generates excessive heat, further breaking down the oil's lubricating properties and leading to accelerated bearing wear.
4. Bearing Damage: The combination of high heat, insufficient lubrication, and increased friction causes premature wear and tear on the rod bearings. The excessive wear can lead to bearing failure, where the bearing material either becomes too thin or collapses completely, resulting in severe engine damage.
5. Connecting Rod Knock: A failed rod bearing produces a distinctive knocking sound when the engine is running. This noise is often described as a deep, rhythmic tapping or knocking coming from the lower part of the engine.
It's essential to address antifreeze contamination in the oil pan as soon as possible to prevent further damage to the engine. To avoid this issue, maintain the proper coolant levels and check for any potential leaks in the cooling system. If you suspect coolant contamination in the oil, drain the oil immediately and replace the oil filter before refilling the engine with fresh oil.
