bushing

Replace when the clearance between the bushing and shaft exceeds twice the original design clearance, or when the surface shows spalling, uneven wear or scoring. Generally, replace when wear of babbitt/copper alloy bushings reaches 5%-10% of wall thickness to avoid seizure and shaft scoring.

Oil seal leakage is mostly due to lip aging and wear, shaft surface roughness exceeding tolerance or scoring, spring failure, or wrong installation direction. Check shaft surface roughness (about Ra0.8) and chamfer, replace with a same-specification oil seal and install the lip in the correct direction.

First check whether grease is too much or too little and whether the grease has deteriorated; then check bearing clearance, mounting and locking, belt tension and alignment. A stable temperature rise within 75°C is normal; above 90°C, stop and inspect immediately.