Screw bolt loose fault performance is bolt loose, re tighten soon, and there is a loose. Causes the transmission shaft bolt to loose the fault to have the following reason:
(1) unbalanced transmission shaft. Transmission shaft imbalance of more than 100 g cm, causing the transmission shaft running in the jitter, due to jitter caused by the drive shaft bolts loose. Because there is no fundamental solution to the problem, only for a simple tightening, the use of a long time and there is loose.
Drive shaft balance and the following several aspects: transmission shaft radial runout is too large; due to parts size does not meet the requirements of precision, resulting in flange fork positioning check mouth tight or too loose, the two flanges at install time axis to coincide; transmission shaft tube bending deformation, sag; both ends of the drive shaft universal joint cross shaft center line is not in the same plane, not uniform rotation.
(2) the transmission shaft connection parts do not meet the requirements. The collar diameter of the flange is not in conformity with the diameter of the flange bolt hole is too large; the use of the non qualified transmission shaft bolt, the above these substandard parts will make the clearance is too large. When the engine speed changes, bolt shear stress caused by the swinging in the hole, bolt loosening phenomenon. In particular, the use of ordinary bolts should not be used.
Fault judgment and elimination
(1) jack up the car's rear wheels, to make it off the ground; start the engine to hang the low speed gear, if the drive shaft has obvious jitter phenomenon that is the rotation of the drive shaft is not balanced. Should remove the drive shaft to do balance check.
(2) if the drive shaft without significant jitter phenomenon, we should focus on examination of the connection parts, such as flanges, flange fork, drive shaft bolts, for the unqualified parts, and resolutely not. To prevent the occurrence of transmission shaft breaking off of a serious accident. |