作者： Release Date: 2017-02-16 Author: Click:
Common failures of camshafts include abnormal wear, abnormal sounds, and breaks. The abnormal sounds and breaks often show symptoms of abnormal wear before they occur.
(1) The camshaft is located almost at the end of the engine lubrication system, so the lubrication condition is not optimistic. If the oil pump has insufficient oil supply pressure due to long usage time, etc., or the lubricating oil passage is blocked, the lubricating oil cannot reach the camshaft, or the tightening torque of the bearing cover fastening bolts is too large, and the lubricating oil cannot enter the camshaft clearance. Causes abnormal wear of the camshaft.
(2) The abnormal wear of the camshaft will cause the gap between the camshaft and the bearing seat to increase, and the camshaft will move axially when it moves, which will cause abnormal noise. Abnormal wear can also cause the gap between the drive cam and the hydraulic lifter to increase, and when the cam is combined with the hydraulic lifter, an impact can occur, which can cause abnormal noise.
(3) The camshaft sometimes breaks down and other serious faults. Common reasons include the cracking or severe wear of the hydraulic tappet, bad lubrication, poor camshaft quality, and cracked camshaft timing gear.
(4) In some cases, the failure of the camshaft is caused by man-made reasons, especially when the camshaft is not properly disassembled during engine maintenance. For example, when removing the camshaft bearing cover, use a hammer to knock it hard or use a screwdriver to pry, or install the bearing cover in the wrong position, which will cause the bearing cover to mismatch with the bearing seat, or the bearing cover tightening bolt tightening torque will be too large. When installing the bearing cover, pay attention to the directional arrows and position numbers on the bearing cover surface, and use a torque wrench to tighten the bearing cover fastening bolts in strict accordance with the specified torque.