Miller Electric OM-1589 manual Changing Gun Contact Tip and Liner, Gun Drive Assembly Maintenance

11-3. Changing Gun Contact Tip and Liner

1 2

Tools Needed:

4 3

150 437

Remove top cover and open pressure roll assembly.

1 Contact Tip Wrench

Insert wrench into nozzle over contact tip.

2 Compression Nut

Loosen nut. Pull out contact tip.

3Contact Tip

4Nozzle

Pull wire out nozzle and liner should slide out. If necessary, tilt nozzle down to remove liner.

Close pressure roll assembly. Reinstall top cover.

Install new liner and contact tip over wire. Cut off wire at end of contact tip.

Tighten nut just until contact tip is secure. Overtightening nut will damage adapter.

11-4. Gun Drive Assembly Maintenance

3

1

2

Retract wire onto spool.

1Setscrew

2Current Pick-Up Tab

This tab helps prevent burnback caused by welding arcs inside the contact tip. This tab may be re- moved to provide an insulated drive roll. (If tab is removed, a smaller di- ameter contact tip is recom- mended. See options in Parts List.) Lightly grease top of tab before rein- stalling.

3 Drive Roll

Use wire brush to clean drive roll. Install drive roll with desired groove down, and turn drive roll so one set- screw faces flat side of shaft.

4 Bearing

Use wire brush to clean bearing. Line up drive roll groove with bear- ing groove and liner opening. Tight- en setscrews.

If changing drive roll in feeder, see Section 11-2.

Thread welding wire through gun. Close and secure pressure roll as- sembly. Adjust drive roll pressure, if necessary (see Sections 3-13and 3-14). Reinstall top cover.

Tools Needed:
5/16 in	4

Ref. 800 945-A

OM-1589 Page 36