CAT 078-5250 LOCKING COLL

CAT 078-5250 is a Caterpillar genuine axle locking collar (also known as an axle retaining ring/circlip), compatible with the hydraulic pilot valve assembly (such as the 078-0776 spool valve) and fuel injection control module of 3044C/3054C engines, 306E/307E excavators, and 226B3/246B3 skid steer loaders. It is used to fix the axial position of rotating components such as 078-3392/078-3401 bearings, preventing axial movement during operation and ensuring precise mechanism reset and stable pressure regulation.

Cat® 078-5250 is a genuine Caterpillar axle locking collar (also known as an axle retaining ring/circlip), compatible with the hydraulic pilot valve assembly (such as the 078-0776 spool valve) and fuel injection control module of 3044C/3054C engines, 306E/307E excavators, and 226B3/246B3 skid steer loaders. It is used to fix the axial position of rotating components such as 078-3392/078-3401 bearings, preventing axial movement during operation and ensuring precise mechanism reset and stable pressure regulation. Core Parameters and Information

Item Details
Part Model: CAT 078-5250 (0785250) Locking Ring

Structure Type: Shaft-mounted elastic retaining ring (E-type circlip), single-turn open type, galvanized and passivated surface for corrosion protection

Material: 65Mn spring steel, quenched and tempered, galvanized and passivated surface, hardness HRC 42-48

Key Dimensions: Inner diameter 15 mm, free diameter 16.5 mm, thickness 1.2 mm, opening width 3 mm, compatible shaft groove diameter 15 mm, groove width 1.3 mm

Performance Parameters: Radial spring force ≥50 N, axial load ≥200 N, operating temperature -40℃ to +150℃, salt spray test ≥48 hours without red rust

Compatibility Standards: Complies with ISO 898-1, SAE J429, compatible with 078-0776 slide valve, 078-3392/078-3401 Bearings, 078-2642 Retaining Spring

Matching Relationship: Compatible with hydraulic pilot valve assemblies and fuel injection control modules for CAT 3044C/3054C engines, 306E/307E excavators, and 226B3/236B3/246B3 skid steer loaders.

Compatible Models and Application Scenarios

Compatible Equipment: Hydraulic pilot valve assemblies and fuel injection control modules for CAT 3044C/3054C engines, 306E/307E mini excavators, and 226B3/236B3/246B3 skid steer loaders.

Application Scenarios: Installed in the annular groove of the valve core/control shaft, it fits against the end face of the 078-3392/078-3401 bearing to lock the axial position, preventing the bearing and valve core from shifting during rotation and reciprocating motion. Suitable for low-to-medium pressure, medium-speed continuous operation, ensuring rapid valve assembly response and precise positioning.

Matching Installation: Used in conjunction with bearings 078-3392/078-3401, locking collar 078-1844, and fixing spring 078-2642. During installation, use snap ring pliers to open the collar before inserting it into the shaft groove, ensuring it is fully engaged and fits snugly against the bearing end face without gaps.

Installation and Maintenance Points: Clean the shaft groove and installation tools. Inspect the collar for deformation, cracks, and corrosion, ensuring good elasticity of the opening.

Use dedicated external snap ring pliers to open the collar, align it with the shaft groove, and insert it smoothly, ensuring the collar is fully engaged and fits snugly against the bearing end face without axial looseness.

After installation, check that the axial movement is ≤0.05 mm, there is no risk of the collar falling off, and rotating parts are free from jamming or abnormal noise.

Maintenance: Check the collar’s condition every 2000 hours. Replace it immediately if deformation, wear, or corrosion is observed to prevent component displacement and damage due to collar failure.