CAT 068-7875 RING

CAT 068-7875 is a Caterpillar genuine fuel pump tappet shaft elastic retainer ring (pure original factory information, no additional description). It is compatible with the high-pressure common rail fuel pump tappet assembly of C13/C15/C18 engines. It is used for axial positioning of the tappet shaft and the 068-6117 bearing, preventing tappet shaft movement, ensuring stable power transmission to the camshaft and plunger, and avoiding fuel pump injection pressure fluctuations and abnormal component wear caused by axial displacement.

Core Parameters and Information

Item Details
Part Model: CAT 068-7875 (0687875) Elastic Retaining Ring

Structure Type: Open Axial Elastic Retaining Ring (with mounting groove, blackened surface oxidation for corrosion resistance)

Material: 65Mn spring steel (HRC47-51, surface oxidation treatment, salt spray test ≥96 h), Weight: 0.005 kg

Key Dimensions: Inner diameter 20 mm, outer diameter 26 mm, thickness 1.2 mm, opening width 3 mm, groove diameter 22 mm, compatible shaft diameter 20 mm

Performance Parameters: Radial tension ≥500 N, operating temperature -40℃ to 150℃, elastic deformation ≤0.05 mm, fatigue life ≥5×10⁵ cycles

Compatibility Standard: Complies with CAT 5K-8876 retaining ring technical specifications, radial runout ≤0.01 mm

Compatible Models and Assemblies

Compatible Parts: 068-6117 Bearings, 068-5183 bearing, 068-2742 tappet retainer, 067-7842 plunger

Compatible Equipment: CAT 336D2/349D2 excavators, 980K/982M loaders, D8T/D9T bulldozers (C13/C15/C18 engines), used for axial positioning of the tappet shaft of high-pressure common rail fuel pumps

Installation: Two pieces per tappet shaft, installed on both sides of the 068-6117 bearing, and secured together with the 068-2742 retainer to ensure no axial movement of the tappet shaft.

Installation and Maintenance Points: Clean the tappet shaft groove and retaining ring. Check the retaining ring for deformation, cracks, and gaps. The surface roughness of the groove Ra≤1.6 μm, and the groove width tolerance 0-0.02 mm.

Using retaining ring pliers (075-2351), pry open the retaining ring and insert it into the tappet shaft slot, ensuring the retaining ring is fully embedded in the slot and fits snugly against the bearing end face without gaps.

After installation, check that the axial movement of the tappet shaft is ≤0.02 mm, rotation is smooth, the fuel pump operates without abnormal noise or leakage, and the retaining ring is not loose or detached.

Maintenance: Check the retaining ring elasticity every 2000 hours (replace when radial clearance is ≥0.1 mm) to prevent high temperature and impurities from causing retaining ring failure. Replacement should be performed simultaneously with bearing inspection.