Function
In a diesel engine, the main bearings and connecting rod bearings play a crucial role in supporting and ensuring the smooth rotation of the crankshaft. The main bearings are positioned between the crankshaft and the engine block, serving to maintain the crankshaft’s alignment and reduce friction during operation. The connecting rod bearings, located between the connecting rods and crankshaft journals, allow for smooth reciprocating and rotating motion between the piston assembly and the crankshaft.
These bearings are typically made from high-strength, wear-resistant materials such as copper-lead or aluminum alloys, which provide durability under high pressure and temperature conditions. Proper lubrication between the bearing surfaces and the crankshaft is essential to prevent metal-to-metal contact and to minimize wear, vibration, and heat generation.
Precautions During Use
During engine operation, the condition of the main and connecting rod bearings directly affects the engine’s performance and service life. The following precautions should be observed:
Lubrication Management – Ensure the engine oil is clean and of the correct specification. Contaminated or degraded oil can lead to insufficient lubrication, causing bearing wear or seizure.
Regular Inspection – Periodically check oil pressure and listen for abnormal engine noises. Low oil pressure or knocking sounds may indicate bearing wear or damage.
Proper Assembly – When replacing bearings, they must be installed with the correct clearance and torque according to manufacturer specifications to avoid misalignment or excessive friction.
Avoid Overloading – Continuous high load or overspeed operation increases bearing stress and temperature, leading to premature failure.
Cleanliness – Keep all parts and oil passages clean during assembly and maintenance to prevent debris from entering the lubrication system.
Conclusion
Main and connecting rod bearings are vital components ensuring the stable and efficient operation of diesel engines. Regular maintenance, correct installation, and the use of quality lubricants are key factors in extending engine life and maintaining optimal performance.
