HARNESS AS 1071693 - Caterpillar

Introduction
This Special Instruction describes a procedure to repair weld cracks that may occur around the boom tower boss of the E240B and EL240B swing frame.Fabrication of reinforcing plates is required to complete this repair.Do not perform any procedure or order any parts until you have read and understand the information in this Special Instruction.Reference: Service Manual; Parts Manual; and Caterpillar Service Welding Guide, form No. SEBD0512.Weld Parameters
Use AWS E706 electrodes or equivalent.Dry the electrodes in an oven at 300°C (572°F) for a minimum of 30 minutes before using to remove moisture.Procedure
Boom Tower Boss.
Doubling plate dimensions The Doubling Plates are not available from the parts distribution system. Fabricate the Doubling Plate to repair the boom tower boss welds.1. Use the dye penetration process to check for possible cracks.2. Determine the full extent of the crack and grind to form a single "V" groove.3. With a torch and wire brush, thoroughly remove all moisture, oil, and paint film from the areas adjacent to the groove.4. Weld the "V" groove.5. Grind the welded area flush and smooth.
Doubling Plate location on the swing frame.
Section A-A
Section B-B6. Tack weld a Doubling Plate to each swing frame side plate (boom tower plate). Keep a clearance of 1 mm (.04 in) or less between the doubling plate and the side plate.7. Using a wire brush and a torch, clean the Doubling Plates and the area on the boom being repaired. Be sure the weld area is free of moisture, oil and paint before beginning to weld.8. Weld the Doubling Plates. See Section B-B.9. Remove all slag after welding. Apply primer coat and paint using a good quality paint.