TM 10-3530-207-14
Table 4-2. Unit Troubleshooting - continued
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
DARNING SEWING MACHINE
15.
NEEDLE BREAKS.
Check for loose presser foot.
If presser foot is loose, tighten (para.
4-38).
16.
MACHINE VIBRATES.
Step 1.
Check that machine-to-table mounting screws are tight.
If any screws are loose, tighten screws (para. 2-8).
Step 2.
Check for Finch deflection at mid-point of drive belt.
If drive belt is out of adjustment, adjust sewing machine (para. 3-10).
Step 3.
Check for loose or damaged drive pulley or machine pulley.
Notify next higher level of maintenance if any of the above conditions exist.
17.
LAMP DOES NOT LIGHT.
Step 1.
Check that light bulb is broken.
If light bulb is broken, unplug power cord from outlet, remove old bulb and replace.
Step 2.
Unplug power cord from outlet and inspect for frayed or broken insulation and wires.
If cord is frayed or broken, replace lamp (para. 3-12).
18.
MOTOR DOES NOT START.
Use a multimeter and check for 110 Vac at power outlet.
a.
If power is not present, the power or distribution cable may be defective. Test cables (para.
4-60 and 4-61).
b.
If power is present, notify next higher level of maintenance that motor or switch may be
defective.
4-36
