Pfaff 3334 - Adjusting the Cone Clutch of Machines with V-Belt Drive; Troubleshooting

31. Adjusting the Cone Clutch of Machines with V-belt Drive
To adjust the clearance between V-belt pulley (Idler pulley) 1 and drive pulley 7 after
the machine has stopped, loosen the nut of eccentric 5 aiid turn the eccentric to the
right or left by hand pntll the forked clutch lever 3 has pushed the ball-bearing collar
of the V-belt pulley against the arm shaft bearing. Hold the eccentric in this position
with an open-ended spanner and tighten its nut.
Q
1 = V-belt pulley (idler pulley)
2 = Engaging
and disengaging collar
3 = Forked clutch lever
4 = Leaf spring
5 = Adjusting eccentric
6 = Clutch lining
7 = Drive puiiey (take-up spring housing)
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Fig. 28
32. Trouble Shooting
Sewing troubies should rarely occur if aii the instructions given in this book are carefully
followed. If
trouble should nevertheless occur, the following hints wiii heip you locate
the fault.
Machine Skips Stitches:
1. ^Needle bent.
2. Needle incorrectly inserted.
3. Needie too fine for the thread.
4. Needle rise inaccurately timed, or needle set too high or too iow.
5. Shuttle set too far away from needle.
Thread Breaks:
1. For any of the causes enumerated above.
2. Needle point blunt or worn, or burrs and sharp edges on needle plate.
3. Thread caught between tension discs.
4. Poor or knotty thread used.
5. Thread tensions too loose or too tight.
Needle Breaks:
1. Needie bent.
2. Needle too fine for the fabric, or deflected by hard spots in the material.
3. Buffer spring broken.
4. Knives improperly timed.
5. Machine feeds while needle is down in material.
6. Work clamp not in line with needie so that needle strikes buckle or clasp to be
sewn on.
Machine Works Heavily:
1. Uck of oil.
2. Mechanism clogged by inferior iubricants.
3. Pieces of thread jammed in shuttle race.
4. Machine or line shaft belt too long.
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From the library of: Superior Sewing Machine & Supply LLC