1. Thread take-up lever gears

 Once a week, No.2 white oil

2. Connecting rod and front & rear metal parts

 Once a week, No.2 white oil 

3. Needle bar case slide rails

 Once a mouth, butter

Remove cover plate of needle bar case

4. Needle bar sliding parts

 Once a week, No.2 white oil

5. Rotary hooks

 1. 2 times a week, No.2 white oil 

Clean with a brush before oil

6. Gears for rotary hooks

 Once per 2กช3 months, butter

Remove needle bar

7. Driving chain

 Once a week

8. Main shaft of needle bar driver

 Once a week, No.2 white oil

Remove cover plate of needle bar case

9. Frame driving rails

 Once a week, butter

1. Air filter of stop motor driver box

 Once a week

2. Air filter of power supply box

 Once a week

3. Frame guide rails

 Once a week (before oil)

4. Needle bar case slide rails

 Before oil

5. Rotary hooks

 Before oil

 With a brush

6. Thread take-up springs

 Every day

7. Other parts

 Clean properly

Thread take-up spring incomplete contact

Securely couple connectors

Tension base connector incomplete contact

Securely couple connectors

Upper thread breakage timing contact incomplete

Clean and adjust the upper thread breakage timing contact

Frame drive belt is too tight

Loosen

Frame guide rails are clogged with foreign materials

Clean the rails

Frame drive circuit defective

Replace

Memory plate defective

Replace

Overall weight of the frame is excessive

Decrease R, P. M