STUD-PULLER 9U7998 - Caterpillar

Introduction
This instruction provides the necessary information to repair cracks in the frame area of the above models.
Repair Areas. (A) Inside rail assembly on rear crosstube casting. (B) Fuel and hydraulic tank mounts.The following steps will be necessary to perform the repairs.* Removal of fuel and fuel tank.* Removal of hydraulic fluid and tank.* Record the location of the hydraulic tank rear mount; or fabricate a locating fixture, so that the rear mount can be removed.* Removal of hydraulic tank rear mount and cutting windows (openings) in the left and right hand rails.* Cut two windows and fabricate eight backup plates.* Cut ten repair plates.* Installation of plates.* Reweld rear hydraulic tank mount.* Reassemble removed parts.Do not perform any procedure, outlined in this publication, or order any parts until you read and understand the information contained within.Fabrication and Welding Information
Photographs and parts shown are current production. Actual parts for field rework may vary in configuration.
Applying heat to fuel tanks, even when "empty", can result in residual fuel or vapor igniting with explosive force. This can result in injury or death. Do not weld or flame cut on any fuel tank without taking the proper safety precautions. Read the article "Welding on Fuel and Hydraulic Tanks," on page 8 in the March 8, 1972 Service Magazine.
Remove all air, hydraulic, fuel, and electrical lines from the areas to be welded.
Cutting shall be with an air carbon arc torch. Welding shall be as indicated, using the specified electrodes.All parts shall be fabricated from 1E170 Steel or equivalent.Use the following materials as approved substitutes:ASTM A572 Grades 42, 45 and 50ASTM A656 Grade 50ASTM A808 DIN 1700 Grade ST46-3 (For thickness through 30 mm (1.18"), and Grade ST52-3 (For thickness through 50 mm (1.97")AFNOR A35-501 Grade36-4BS 4360 Grades 50B, 50D, and 50EJIS G3106 Grades SM50A, SM50B, and SM50CCSA CAN3-G40.21-M Grades 300W and 350W, and Grades 300WT and 350WTDrain the fuel tank and prepare it for welding as described on page 8 in the March 8, 1972 Service Magazine.1. Remove fuel and fuel tank.2. Remove hydraulic fluid and tank.Necessary Parts
789 Truck Only
Plate 001, two required.
Plate 002, two required.
Plate 003, two required.
Plate 004, two required.
Plate 005, two required.785 Truck Only
Typical chamfer and plate thickness for plates 1, 2, 3, 4, and 5.
Plate 1, two required.
Plate 2, two required.
Plate 3, two required.
Plate 4, two required.
Plate 5, two required.785 and 789 Trucks
Backup Plate, top and bottom, four required.
789 Backup Plate, sides, four required.* Dimension (X) 785: 111 3 mm (4.37 .12 in).* Dimension (X) 789: 196 3 mm (7.72 .12 in).
Window Plate, two required.* Dimension (Y) 785: 365 4 mm (14.37 .16 in).* Dimension (Y) 789: 450 4 mm (17.72 .16 in).Fuel and Hydraulic Tank Mounts
Hydraulic tank mount.
Fuel tank mount.
(C) Weld seam.1. Cut a window on the fuel tank side per dimensions shown. Window plate may be used again to close opening.* Dimension (Z) 785: 385 (15.16 in).* Dimension (Z) 789: 470 mm (18.50 in).2. Cut off the hydraulic tank