FLYWHEEL A. 5M4139 - Caterpillar

Series "
G"
Motor Graders Equipped With A Circle Drive Slip ClutchReference: Service Magazine; February 9, 1981; Page 2; "Slip Clutches Now Available On Circle Drive Group." Service Magazine; March 16, 1981; Page 8; "Supplements." When a circle drive slip clutch is repaired or a new clutch is installed, use the procedure in the reference articles to adjust the initial spring deflection.
Use the procedure that follows to check the circle drive slip clutch.
1. Use a suitable immovable object ("dead man") on a flat concrete floor that is clear of any objects. Be sure to fasten the operator's seat belts.2. Center the draw bar with the frame. Lower the blade to within 25.4 mm (1.00") of the floor. Position the blade perpendicular to the frame. Extend the blade all the way to the right or left.3. Bring the blade in contact with the immovable object on the floor with no more than 305 mm (12.0") of blade beyond the center line of the immovable object.4. Lock the differential on motor graders so equipped.5. With the transmission modulation pedal engaged, select the third forward speed. Raise the engine rpm to high idle and release the modulation pedal. The circle drive slip clutch should slip.6. If the circle drive slip clutch does not slip, the following procedure must be used to break the clutch loose.a. Position the machine so the blade is 460 to 610 mm (18.0 to 24.0") from the immovable object.b. With the transmission modulation pedal engaged, select the third forward speed. Raise the engine rpm to high idle and release the modulation pedal.c. The circle drive slip clutch should slip. If the circle drive slip clutch does not slip, the clutch needs to be adjusted. Reduce the number of shims to tighten the slip clutch. Add shims to loosen the slip clutch.7. If the slip clutch slipped when Step 6 was performed, repeat Step 5. If the slip clutch did not slip, make adjustments as necessary.8. Repeat Steps 3 and 4. Then, with the transmission modulation pedal engaged, select the fifth forward speed. Raise the engine rpm to high idle and release the modulation pedal. The slip clutch should not slip and the engine should stall.