Pfaff 261 Owner's Manual - Page 32

6. Machine Works Heavily Cause: Motor belt is too loose, or has shrunk and causes excessive pressure on bearings. Hook raceway lacks oil or is obstructed by pieces of thread. Mechanism clogged by inferior oil. Machine works heavily when automatic embroldery mechanism is engaged. Bobbin winder working while sewing (when a bobbin is not being filled). Remedy: Have your Pfaff dealer adjust the belt tension. Clean and oil hook raceway. Use only Pfaff sewing machine oil -- never salad oil or glycerine. See note on page 8. Stop bobbin winder. 7. Stopmatic Works Incorrectly Cause: After frequent operation of the Stopmaiic it may happen that the take-up lever does not move when you push the presser bar lifter up all the way. Take-up lever strikes hard against its stop or does not rise when Stopmatic lever is operated. Remedy: The built-in thermal switch may have interrupted the electric circuit. Wait a few minutes until both the motor and the thermal switch have cooled down and the electric circuit has been closed automatically. Have your Pfaff dealer adjust the Stopmatic. Note the "Fundamentals of Machine Operation" on page 4. Thread Jamming The new Pfaff rotary hook will not normally jam, even if the machine should be handled improperly. If thread should happen to jam in the raceway of the sewing hook, the power of the motor in most instances will be sufficient to overcome hard working of the mechanism. If this action should not free the jammed thread, put a drop of kerosene into the hook raceway, jerk the balance wheel back, then jerk it back and forth. Thread jamming can be avoided, however, if you follow the instructions on page 4. 31