1. Whether the engine is leaking oil, whether the black smoke is very large when the accelerator is increased, whether the sound is abnormal, whether it is abnormal.
2. The strength of the hydraulic pump, the engine is at idle, the excavator is propped up, and the hydraulic pump is not strong or the engine sound is abnormal when it is propped up. Step up the throttle and stretch out all cylinders to see if the hydraulic pump changes sound.
3. Track plate detection.
4. The excavator turntable around, the upper and lower clearance check, allowing a little gap around, but not up and down.
5. Look at the number of tubing replaced by the excavator, the less proof that the excavator is new.
6. Normal throttle speed check.
7. Check all cylinders to see if there are scars.
8. Walking check, prop up the side, walk adjusted to high-speed mode, ear close to the driving wheel to listen to the sound is abnormal.
9. Look in the cab.Don't look at the hour table, to work practical is good! The main thing is to look at the engine.