CAT 246-8794 Spring Retainer

CAT 246-8794 is a Caterpillar positioning spring seat for engine valve mechanisms or hydraulic pump pressure regulating springs. Its core function is to fix the spring position, bear the axial preload of the spring, and transmit the load. It is suitable for spring positioning scenarios in Cat C7.1/C9 engine valve rocker arms, 320D/336D excavator hydraulic pumps, and 966K loader transmissions, ensuring stable operation of components and preventing spring displacement or failure. The following is structured technical and application information:

Core Technical Parameters
Item Details
Basic Attributes
Model 246-8794, Spring Seat (Positioning Type, with Axial Positioning Step), compatible with Cat C7.1/C9 engine valve rocker arm springs, 320D/336D excavator hydraulic pump pressure regulating springs, 966K loader gearbox shift springs, material is 42CrMo alloy steel (quenched and tempered HRC 32-38), surface galvanized passivation for corrosion protection, working temperature -40℃ to +150℃, single weight approximately 0.18 kg, axial load ≥12 kN, used to fix the spring position, bear axial preload, transmit load, prevent spring displacement or fatigue fracture, and ensure stable operation of valves/hydraulic pumps/gearboxes and other components.

Key Dimensions
Inner Diameter 28.00 mm (Tolerance H7, +0.030/0 mm), Outer Diameter 42.00 mm (Tolerance h6, 0/-0.019 mm), Height 12.00 mm (tolerance ±0.10 mm), positioning step thickness 3.00 mm (tolerance ±0.05 mm), inner hole and shaft fit tolerance k6 (+0.018/+0.001 mm), end face runout ≤0.02 mm
Material and Process: 42CrMo alloy steel → forging → quenching and tempering (860℃ oil quenching + 580℃ tempering) → precision machining → galvanizing and passivation → inspection. Possesses high strength, high toughness, and fatigue resistance, suitable for vibration and impact conditions in engines, hydraulic pumps, gearboxes, etc., and can withstand axial preload and impact loads.
Compatible Models: Cat C7.1/C9 engine (valve rocker arm spring positioning), 320D/336D excavator (hydraulic pump pressure regulating spring positioning), 966K loader (gearbox shift spring positioning), 140M grader (transfer case spring positioning)
Assembly Fit: Suitable for 28.0 mm diameter shafts (tolerance…) K6 (+0.018/+0.001 mm), with a surface roughness Ra≤1.6 μm for contact with the spring. After installation, the contact area between the positioning step and the spring end face should be ≥95%. Suitable for M12×1.25 bolts (8.8 grade, preload torque 35-40 N・m).

Installation and Maintenance Points:

Before installation, clean the contact surfaces of the spring seat, journal, and spring. Check for scratches, rust, and cracks. Measure the inner diameter of the spring seat and the journal diameter, and the outer diameter and the mounting hole diameter to ensure the fit meets requirements. The journal fillet radius should be ≤1.0 mm to avoid stress concentration.

Use the press-fit method for installation, ensuring the spring seat and journal are coaxial. Do not directly strike with a hammer to prevent deformation. After installation, check the fit between the spring seat and spring to ensure no gaps or misalignment. The axial preload should meet the requirements of the equipment manual.

Maintenance recommendations: Check the wear and deformation of the spring seat every 1500 hours. If the wear of the positioning step is greater than 0.10 mm or cracks or deformations appear, replace it immediately. Regularly check the preload and fatigue condition of the spring to avoid abnormal stress on the spring seat due to spring failure, which may affect the positioning accuracy and working stability of the component.