Usage:
120G, 130G, 140G, 12G Motor Graders
There have been reports of the scarifier mounting plates coming loose that attach the scarifier to the motor grader frame. These parts can be modified to make the mounting plates more permanent and prevent them from coming loose. Use the method that follows to modify the scarifier mounting plates.
1. Remove the scarifier lift links and lift cylinder shown in Illustration 1.
Illustration 1. Scarifier lifting components.
2. Remove the four bolts that hold the lift arm bracket assembly and mounting plate to the frame. Remove the lift arm bracket assembly and mounting plate shown in Illustration 1.
3. Remove the three bolts and the scarifier check-relief valve. Remove four bolts and the lift cylinder mounting bracket. See Illustration 2.
Illustration 2. Location of check-relief valve and lift cylinder mounting bracket.
4. Use an air carbon arc torch or similar tool to remove the two spacer plates from the scarifier lift arm mounting plate. See Illustration 3. Grind the plate smooth.
Illustration 3. Location of spacer plates to be removed from the lift arm mounting plate.
5. Make four slots in the lift arm mounting plate using the dimensions given in Illustration 4.
6. Cut off the check-relief valve mounting portion (X) of the lift cylinder mounting plate as shown in Illustration 5.
Illustration 4. Dimensions for making the slots in the lift arm mounting plates.
7. Modify the lift cylinder bracket so it is similar to the area market (Z) in Illustration 5.
Illustration 5. Location of check-relief valve mounting.
8. Make a new check-relief valve mounting plate from portion (X) in Step 6. Use the dimensions given in Illustration 6.
Illustration 6. Dimensions for the new check-relief valve mounting plate.
Illustration 7. Top view of motor grader frame with dimensions for welding mounting plates.
9. Position the lift arm mounting bracket on the motor grader frame as shown in Illustrations 7 and 8. Make sure the distance from the holes in the mounting plate to the motor grader frame are equal on either side. Weld the mounting plate in place using the dimensions in Illustration 7. DO NOT MAKE ANY WELDS ACROSS THE MOTOR GRADER FRAME.
10. Weld the lift cylinder mounting bracket to the motor grader frame as shown in Illustrations 7 and 8. Be sure the bracket is centered on the frame. DO NOT MAKE ANY WELDS ACROSS THE MOTOR GRADER FRAME.
11. Weld the check-relief valve mounting plate, made in Step 8, to the motor grader frame as shown in Illustration 7.
12. Mount the scarifier group on the motor grader. It may be necessary to build up the stop, on the lift arm mounting plate, with weld to prevent the lift cylinder from going over center when it is retracted.
Illustration 8. Side view of the motor grader frame with dimensions for the new mounting plates.