SPACER 3870722 - Caterpillar

Crack/Surface Preparation
Use an electric or pneumatic grinder with a carbide cutter to remove the crack as shown in Illustration 3 through Illustration 5. Round off the edges and corners of the cut to avoid stress points. Do not use a grinding wheel. The abrasive grains can embed into the surface and interfere with weld fusion.
Illustration 3 g02271233
Crack in the web area
(1) Typical crack location
Illustration 4 g02271234
Web area after the crack has been removed.
(2) Rounded corners
Illustration 5 g02271235
Inspect the area visually to make sure that the crack has been removed.
Clean all oil, grease, paint, dye penetrant, and so on, from the area affected by heat. Remove surface oxides from the area that is to be repaired.Note: Good cleaning and surface preparation is important, if a good quality repair is to be made.Preheat
Preheating or postheating of the area for repair is not required. For this welding procedure, the carriers should be at room temperature, approximately 20 °C (68 °F), and must be protected from all drafts, especially in cold weather.Welding Instructions
Personal injury or death can result from fumes, gases and ultraviolet rays from the weld arc.Welding can cause fumes, burn skin and produce ultraviolet rays.Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing area. Wear eye, ear and body protection before working.Protect yourself and others; read and understand this warning. Fumes and gases can be dangerous to your health. Ultraviolet rays from the weld arc can injure eyes and burn skin. Electric shock can cause death.Read and understand the manufacturer's instructions and your employer's safety practices. Do not touch live electrical parts.See "American National Standard Z49.1, Safety in Welding and Cutting" published by the American Welding Society.American Welding Society
2501 N.W. 7th Street
Miami, Florida 33125
See "OSHA Safety and Health Standards, 29 CFR 1910", available from U.S. Department of Labor.U.S. Department of Labor
Washington, D.C. 20210
Note: Be sure the surface to be welded has been correctly cleaned and prepared for the repair procedure. Refer to the topic, "Crack/Surface Preparation", in this guideline. After completing the preparation, use the procedure that follows.
Put a 1U-6339 Polarity Tester on the carrier, and touch the welding electrode to the metal disc to check the polarity of the welding machine. See Illustration 4. The LED readout will indicate negative (-) for straight polarity or positive (+) for reverse polarity.
Illustration 6 g02271335Note: Straight polarity allows for shallow penetration, less heat input, and increased weld deposit. Reverse polarity has greater heat input, more penetration, and more dilution of the base material. When welding cast iron, make sure that the correct polarity for the weld material being used to get the desired results.
Mask the planetary shaft bores and thrust faces to protect from weld spatter.
Stick Electrode: Set the welding machine for DC straight [negative (-)] polarity and 45 amps. (Verify the current setting by doing welding on a piece of scrap.) Use 1U-5379 Weld Rod, 2.0 mm (0.08 inch) diameter. The weld deposit must not be more than twice