to the vertical motion of the needlebar. Remove the needlebar connecting link by grasping it and then withdrawing it from the face of the machine.
The balance-wheel adjusting screw (figure 4-11 [L]) eliminates end play in the balance wheel and arm shaft. Remove the balance wheel adjustment screw.
The balance wheel (figures 4-6 [R] and 4-11 [N]) transfers the motion and power from the one- third-horsepower electric motor to the arm shaft. To remove the balance wheel, you must first loosen the two setscrews attaching it to the arm shaft; then you withdraw it from the machine.
NOTE: The balance wheel is very fragile. Do not hit it with a hammer to remove it.
The arm shaft connection belt (figure 4-4 [A]) transfers the power and motion from the arm shaft connection belt pulley to the safety clutch pulley. To remove the arm shaft connection belt, you insert a small screwdriver along the left edge and slide the belt from the safety clutch pulley.
The arm shaft connection belt pulley position screw holds the pulley in a freed position. The arm shaft connection belt pulley position screw is the larger of the two screws on the pulley. The smaller screw is a setscrew. It must be loosened but not removed from the pulley. Remove the arm shaft connection belt pulley position screw by unscrewing it.
NOTE: For machines with ball bearings, the arm shaft arm bushing setscrews are located just to the right of the connection belt pulley. They secure the arm shaft bushing to the arm shaft. These screws are not removed from the bushing; however, they must be loosened for the arm shaft to be removed.
The presser-lifting eccentric supplies the lift for the alternating presser feet. Free the presser-lifting eccentric by loosening the two presser-lifting eccentric setscrews located through the opening in the rear of the arm (figure 4-11 [A]). You must rotate the balance wheel to loosen the second screw. Be sure the eccentric rotates freely on the shaft.
The feed indicator disc shows the operator the number of stitches per inch the machine is sewing. It also allows the operator to set the machine to sew a desired number of stitches per inch. Loosen the feed indicator disc setscrew and ensure the disc will rotate freely on the shaft.
The needlebar crank transfers the motion and power from the arm shaft to the needlebar by the needlebar driving stud. Do not remove the needlebar crank from the arm shaft.
The needlebar connecting link stud transfers the motion and power from the needlebar crank to the needlebar connecting link. Do not remove the needlebar connecting link stud from the arm shaft.
The needlebar crank friction washer acts as a bearing surface between the needlebar crank and the front arm shaft bushing. In some cases the needlebar crank friction washer remains with the machine upon removal of the arm shaft bushing. If this occurs, insert the index finger in the arm shaft recess and remove the washer.
NOTE: The operator must be especially careful when assembling the machine to be certain the needlebar crank friction washer is returned to the armshaft. Absence of the needlebar crank friction washer will cause the machine to bind.
The arm shaft (figure 4-11 ) acts as a carrier for, and transfers the power and motion to, the arm shaft connection belt pulley, the feed indicator disc, the needlebar crank friction washer, and the needlebar crank. To removeContinue Reading