TM-9-2350-274-BD

M109/M110/M578 VEHICLES HOWITZER, MEDIUM, SELF-PROPELLED FULL-TRACKED

TECHNICAL MANUAL; OPERATORS, ORGANIZATIONAL DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE

JANUARY 1984

TM-9-2350-274-BD - Page 121 of 219

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