Fault:
Body vibrated badly
Cause:
1. Insecure suspension of main engine
2. Fan installation is not in place
3. Fan damaged
4. Loose hand nut
How to do:
1. Make sure the main engine is firmly hung
2. Install the fan in place
3. Replace the fan (contact the after-sales service center)
4. Tighten the hand nut to ensure no loosening