Answer: (1) Cause analysis.
1) The oil seal falls off or the oil seal is defective and leaks oil;
2) The main shaft fixed bearing is worn, causing the oil seal to leak oil;
3) The joint surface leaks;
4) The oil inlet and return pipe joints are loose;
5) Casting or processing defects;
6) The transmission belt is installed with too much tightening force, which increases the gap on one side of the oil seal.
(2) Elimination method.
1) Oil seal part. Check the matching dimensions of the oil seal, sleeve, and housing, and replace those that do not meet the standards; Move the driving shaft with force to check whether the radial clearance is too large. If the clearance is too large, replace the sleeve and oil seal at the same time; Check whether the joint surface between the oil seal and the sleeve is scratched or defective. If there are scratches and defects, replace it.
2) Check whether the oil seal is cracked and whether the inner lip is cracked or flanging. If any of the above situations occurs, replace the oil seal and further check the main shaft bearing.
3) Check the sealing condition of the gaskets at each joint, and repair or replace the gaskets.
4) Check the oil inlet and return joint bolts and the box thread and tighten them.
5) Check the defects in the casting or processing of the box (such as whether the oil return hole at the installation of the box oil seal is unobstructed), and repair or replace the defective parts.
6) Check and readjust the belt tightness, and the thumb is preferably 10mm.
