Replacing The Piston - Duerkopp Adler 743-221 Service Manual

3.1.2

Replacing the piston

24
6
7
1
The moving blade is raised pneumatically.
The piston 4, which operates the blade, is located in the body of the
clipper.
Regulation and inspection
When the piston is replaced it must be adjusted so that the edge of the
moving blade is just beneath the edge of the fixed blade 12.
Caution: danger of injury
Turn off the main switch.
The thread clipper may only be removed with the sewing machine
switched off.
The piston may only be replaced when the thread clipper has been
removed.
IMPORTANT !
The surface of the hole is anodised.
When replacing the piston take care not to damage the anodised layer.
Adjustment
–
Remove thread clipper (see section 3.1).
–
Remove retaining ring 1.
IMPORTANT !
Washer 2 is under spring pressure.
–
Remove washer 2, pressure spring 3 and piston 4 with O-ring 5.
–
Grease the surface of the hole with ESSO S420 grease.
(Order no.: 0791 000304)
–
Re-assemble the piston in the reverse order.
If this screw 11 has been unscrewed it must be replaced in the hole
together with PTFE tape (see section 3.1.1).
–
Fit the thread clipper.
–
Carry out a cutting test with sewing threads (test program).
2 3 4 5 6 7