SHAFT 3041884 - Caterpillar

Whenever the load lift arms are near or above the horizontal plane, it is possible to extend the tilt cylinder to its fullest extent before bucket stops make contact. This may damage the cylinder and rods if pressure is applied to the cylinder or bucket when they are in this position.Whenever the tilt cylinder is fully extended, the rod piston will contact the forward end of the tilt cylinder. If the tilt cylinder must be fully extended (as in the loading of some hoppers), damage to the cylinder and rods can be prevented. Make sure that the rod pistons contact the forward end of the cylinder with a very soft impact to prevent cylinder damage.
Note: The rack back stops should be checked prior to installing a different bucket, lift arms or tilt cylinders.
With the bucket on the ground, tilt the bucket backward until the rack back stops contact the lift arms.
Slowly raise the bucket.
Stop raising the bucket when the rack stops on the bucket start to pull away from the lift arm.
The bucket should be approximately 2.1 m to 2.4 m (7 ft to 8 ft) (Z) off the ground when the distance is measured from the center or the bucket pin (B) to the ground.Note: If material needs to be added to one or both bucket stops, use mild steel and only weld in the vertical direction.Note: If material needs to be removed from one or both bucket stops, a torch can be used. The surface needs to be ground smooth after using a torch. Any depression will cause a stress riser which can promote cracking.Note: If the rack back stops stay in contact with the lift arm to a height higher than 2.4 m (8 ft), the rack back stops will provide more protection for the tilt cylinders, but the rack back stops may adversely affect the filling of the bucket.Note: If the rack back stops do not stay in contact with the lift arm until 2.1 m (7 ft), the result could be failure of the head bolts on the tilt cylinder in certain applications.
If the linkage stops show signs of deformation along the edges, a grinder can be used to smooth out those edges.Note: Do not weld on the lift arm stops.Note: If the lift arm stops have any depressions from bucket stop wear, a grinder can be used to smooth out the transitions on the lift arms.
Illustration 1 g01198623
Rack back stops.