BUCKET AS-HOE 2322755 - Caterpillar

Gray Discoloration
The intensity of gray on some connecting rods and main bearings is caused by the variation in thickness of the tin flash that is electroplated onto the bearings. The flash protects the steel back of the bearings from corrosion. The bearings have a specification of thickness that requires a maximum of 2.5 microns. If the thickness is 0.5 microns or less, the overlay of lead and tin will penetrate through the tin flash. This will cause the intensity of the color to vary. Gray discoloration has no effect on the function of the bearing. Bearings that have a gray discoloration are acceptable to use.Note: With enough time and temperature, the flash material will dissipate into the material of the overlay. This dissipation is a natural process of age.Brown Discoloration
The brown discoloration is caused by a chemical reaction between condensation and deposits on the surface of the bearing. This may lead to corrosion on the bearing surface. Do not use bearings that display brown discoloration. Refer to the illustrations below.Bearings that Are Unacceptable for Use
Do not use any bearing with any of the following conditions:
Areas of brown discoloration
A sharp, distinct border between light gray areas and dark gray areas
Any purple areas or blue areasNote: Do not confuse brown discoloration with a rust preventive that is applied at the supplier. The rust preventive adds additional corrosion protection during shipment. Follow the cleaning procedure in Reuse and Salvage Guideline, SEBF8009 in order to determine if the discoloration is a rust preventive.Bearings that Are Acceptable for Use
Bearings with the following conditions are suitable for use:
Gray discoloration that changes in intensity from light gray to dark gray without a sharp, distinct border
Discoloration on the sides of the bearings is acceptable because the side of the bearing is not part of the rotating element of the design.
If the residue of water can be removed, follow the procedure that is outlined in Reuse and Salvage Guideline, SEBF8009.
Illustration 1 g01357517
(1) Material code
Illustration 2 g01348848
The bearing has a large amount of stain on the surface of the bearing. Do not use the bearing. Refer to Illustration 2.
Illustration 3 g01351807
The bearing indicated that the corrosion (2) has penetrated the tin overlay. Refer to Illustration 3.
Illustration 4 g01366635
The bearing indicated that the corrosion (3) has penetrated the tin overlay. Do not use the bearing. Refer to Illustration 4.
Illustration 5 g01366645
The bearing has stain (4) on the surface. Do not use the bearing. Refer to Illustration 5.
Illustration 6 g01366646
The bearing indicated that the corrosion (5) has penetrated the tin overlay. Do not use the bearing. Refer to Illustration 6.
Illustration 7 g01366651
The bearing indicated that the corrosion (6) has penetrated the tin overlay. Do not use the bearing. Refer to Illustration 7.
Illustration 8 g01366652
Any stain on the edge or corrosion on the edge of the bearing (7) is acceptable. Refer to Illustration 8.
Illustration 9 g01366654
The bearing has stain (8) on the surface. Do not use the bearing. Refer to Illustration 9.