1. The oil level in the oil and gas separator is too high; remove part of the lubricating oil to reduce the oil level to the specified height. Observe the oil level gauge while the machine runs to determine the oil level.
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2. The secondary oil return pipe is blocked; clean the oil return pipe and whether the oil return check valve is damaged.
3. Exhaust temperature is too high;
4. Improper adjustment of the oil return pipe; adjust the distance between the oil return suction pipe and the bottom of the separator core to ensure that the end of the suction pipe is made 45°.
5. The oil separator core is damaged;
6. Lubricating oil pipeline leakage;
7. Seal failure;
8. The loading and unloading cycles are too frequent;
9. Improper use of lubricating oil;