How to adjust the bearing clearance when the automobile differential is loud?

When repairing the automobile differential, i query learned a lot about how to adjust the bearing clearance. It is said that many of them are problematic, incomplete and incorrect. Later, I finally found a more comprehensive and professional article, and now I will introduce it to you. I hope that through these introductions, you will have a deeper understanding of the causes of bearing clearance and a more comprehensive understanding of the methods to deal with bearing clearance. I sincerely hope I can help you! The axial clearance of crankshaft can be achieved by scraping the surface of thrust alloy or replacing thrust bearing shells with different degrees. If the gap is too small, scrape the surface of thrust alloy; If the gap is too large, replace the thrust bearing bush, adjust the thicker thrust bearing bush or plate a layer of alloy on the thrust bearing bush. Crankshaft bearing noise is mainly caused by clearance. Phenomenon: 1) Under normal circumstances, there is no noise when the engine runs stably, and when the engine speed changes suddenly, it makes a dull "muffled" knocking sound accompanied by vibration. 2) When the engine load changes, the noise is obvious. The higher the speed, the louder the noise. 3) No change can be felt when a single cylinder is turned off, but the noise will be obviously reduced when two adjacent cylinders are turned off at the same time. Cause: 1) The fit clearance between crankshaft and journal is too large. 2) The gap between crankshaft and axial direction is too large. 3) The crankshaft bearing cap bolt is loose. 4) Poor lubrication of crankshaft bearing and journal leads to ablation and shedding of bearing alloy. 5) The crankshaft is bent and deformed, and the crankshaft journal is not round. 6) Crankshaft bearing and bearing seat rotate relatively. Diagnosis: 1) The sound comes from the lower part of the cylinder block near the crankcase. The oil pressure dropped significantly. The engine vibrates the throttle valve at low and medium speed, and the continuous knocking sound is obvious and dull with the engine vibration. 2) When the engine is running at high speed, the vibration of the engine body is great, and the oil pressure drops obviously, indicating that the gap between the bearing and the journal is too large or the bearing alloy is ablated. 3) The sound of single cylinder flameout test has little change, but the sound of adjacent two cylinders is obviously weakened or disappeared during flameout, indicating that the crankshaft bearing between the two cylinders is ringing. 4) When the rotating speed is not high, the body vibrates greatly, and there is a phenomenon of swaying. At the same time, a heavy and loud "bang" knocking sound is that the crankshaft is broken. 5) The noise increases with the increase of temperature. At high speed, the noise becomes chaotic, which may be the crankshaft bending. It depends on the specific situation! I wish you good health. When the meshing mark is biased towards the big end, the driven gear will approach the driving gear. If the backlash is too small, the driving gear will move outward. When the engagement mark is biased to the small end, move the driven gear away from the driving gear. At this time, if the backlash is too large, please move the driving gear closer. When the meshing mark is biased towards the tooth top, the driving gear moves closer to the driven gear, and if the gap is too small at this time, the driven gear moves outward; When the meshing mark is biased towards the tooth root, the driving gear is far away from the driven gear. If the gap is too large at this time, the driven gear moves inward. Summarized a jingle, the direction of gear movement: big advance from the main; Small from, top into the Lord; Top into the Lord, small out from; Rooted in the Lord, great progress from. Just look at the inkpad on the picture, mainly looking at the contact surface between the driven gear and the driving gear. If the adjustment is not good, it will be seriously worn. The bearing clearance cannot be adjusted, and the differential can be adjusted by the longitudinal back and forth movement of the driving gear and the driven gear. This is also an important technology in car repair! Ha ha! ~~