TM-9-2350-274-BD M109 Battlefield Damage Assessment and Repair Download
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TM 9-2350-274-BD TRACK AND SUSPENSION 9-6. DRIVE SPROCKET BOLTS SHEARED OFF General Information: The final drive sprocket bolts can work loose allowing the sprocket to shift and shear part or all of the mounting bolts, resulting in the track being thrown. If new mounting bolts are not available the sprocket can be remounted by obtaining bolts from the other side of the vehicle. At least five of the ten mounting bolts must be installed. If a sufficient number of bolts are not available the sprocket can be welded to the hub. If the full amount of mounting bolts are not used or the sprocket is welded pivot steer should not be used. The side stress could cause the bolts or weld to shear. Limitations: ● If welded, reduced mobility Personnel/Time Required: ● 2 soldiers ● 1-2 hours Materials/Tools ● Replacement sprocket bolts, nuts ● Welding equipment ● Lift capability Procedural Steps: 1. Separate track to allow access to drive sprocket assembly (item 1). 2. Remove drive sprocket and hub assembly from final drive assembly. 3. Remove loose damaged bolts (item 2) and nuts. Clear holes of inside and outside sprockets and hub of remains of sheared bolts. 4. Properly align and use replacement bolts or weld sprockets to hubs. 5. Mount repaired hub and sprocket back onto final drive assembly. 6. Reconnect track and adjust tension. 7. Record the BDAR action taken. When mission is completed, as soon as practicable, repair vehicle using standard maintenance procedures. Change 1 9-5 SECTION III. Drive and Roadwheels