CAT 8P-1758 100mm Inner Diameter Bearing Retainer

CAT 8P-1758 is a Caterpillar genuine hydraulic torque converter housing-specific bearing retainer (bearing race), made of high-strength gray cast iron. It is used to position and support the torque converter input shaft/guide wheel shaft end bearing, preventing bearing runout and movement. It is compatible with the torque converter assemblies of medium and heavy-duty loaders and excavators. The following are the key information.

Core Technical Parameters

Item Details
Part Model: CAT 8P-1758 (Bearing Retainer/Bearing Seat Ring, One-piece Gray Cast Iron, with Locating Stop and Mounting Flange)

Material: HT250 Gray Cast Iron, Tensile Strength ≥ 250 MPa, Hardness HB 190-240, Surface Anti-corrosion Coating, Suitable for -40℃ to +120℃ Operating Conditions

Key Dimensions: Inner Diameter 100 mm (3.937 in), Outer Diameter 150 mm (5.906 in), Thickness 22 mm (0.866 in), Stop Diameter 120 mm (Locating Bearing Outer Ring), 6 Evenly Distributed Mounting Holes (Suitable for 3/8 in Bolts, Hole Spacing Φ130 mm)

Unit Weight: Approx. 1.8 kg (3.968 lbs)

Tolerances and Geometric Forms: Inner Diameter Tolerance H7 (0/+0.035 mm), Stop Tolerance h6 (0/-0.022 mm), mounting surface flatness ≤ 0.05 mm, coaxiality ≤ 0.03 mm
Core Functions: Radial positioning of the bearing outer ring and axial restriction of bearing movement, providing stable support for the rotating components of the torque converter, reducing vibration and noise, suitable for medium- and high-speed, continuous load conditions.
Structure and Core Functions:

Precise Bearing Positioning: The integrally formed stop fits the bearing outer ring (0.010-0.020 mm), preventing radial runout of the bearing in the torque converter housing, ensuring the coaxiality of the input shaft and guide wheel shaft, and reducing abnormal wear of the rollers and raceways.

Axial Limitation and Anti-Movement: The flange end face fits against the bearing outer ring end face, and with the bolt preload, the axial displacement of the bearing is limited (≤0.05 mm), preventing the bearing from impacting the housing during torque converter operation and extending the life of the bearing and housing.

Uniform Load Transfer: The gray cast iron material has good damping properties, absorbing the vibration generated by the high-speed rotation of the torque converter, while uniformly transferring the radial load of the bearing to the housing, reducing local stress concentration.

Easy Assembly: Six evenly distributed mounting holes accommodate 3/8-inch high-strength bolts. Quick positioning via the retaining groove during installation eliminates the need for additional alignment, improving assembly efficiency.

Compatible Models and Application Scenarios

Compatible Equipment: CAT 966M/972M loaders, 336GC/349GC excavators, 450F2 backhoe loaders, torque converter assemblies for C13/C15 engines.

Core Application: Installed at the front/rear bearing mounting positions of the torque converter housing, supporting the input shaft front bearing and the guide wheel shaft support bearing. Suitable for torque converter input speeds of 0-2500 rpm, ensuring smooth power transmission.

Installation and Maintenance Points

Installation: Clean the retaining groove, mounting surface, and housing mating surfaces, ensuring no burrs or oil contamination. Apply a thin layer of high-temperature grease to the retaining groove. After heat-fitting the bearing outer ring (80-100℃), insert it into the retaining groove, ensuring a tight, gapless fit.

Use CAT genuine 3/8 in high-strength mounting bolts, pre-tighten them in a crisscross pattern to a torque of 35-40 N·m, and check the bearing axial clearance after installation (≤0.05 mm).

Maintenance: Regularly check the bolt torque and retighten them every 1000 hours; monitor the torque converter housing temperature, and if it exceeds 95℃, stop the machine and check the fit between the retainer and the bearing.

When replacing the bearing, simultaneously check the wear of the retainer stop. If the wear of the stop diameter exceeds 0.10 mm or the flatness of the mounting surface exceeds 0.10 mm, the retainer must be replaced to prevent bearing positioning failure.