CAT 3G-8136 Cylinder Seal Retainer

CAT 3G-8136 is a Caterpillar cylinder block/pump body shaft seal ring (PTFE + elastomer composite structure), adapted for sealing the shaft bores of engine cylinder blocks and hydraulic pump housings to prevent high-pressure oil leakage and contaminant intrusion. The following is professional structured information.

Core Parameters (Professional Version)

Project Details
Basic Attributes
Model 3G-8136, Shaft Static Seal Retaining Ring (Anti-Extrusion/Anti-Leakage), Quantity per Unit: 1–2 pieces, Suitable for Cat C7.1/C9.3 Engine Cylinder Block Crankshaft Rear Oil Seal Seat, 320D/336D Excavator Hydraulic Pump Housing Shaft Hole, Provides Static Seal + Slight Dynamic Compensation, Suitable for High Pressure (≤40 MPa) and Medium Temperature Conditions

Key Dimensions
Inner Diameter 100 mm, Outer Diameter 115 mm, Thickness 5 mm, Edge Width 3 mm, Chamfer C1×45°, Suitable Shaft Diameter 100 mm, Seat Hole Diameter 115 mm, Groove Width 5.2±0.1 mm, Groove Depth 3.2±0.05 mm, Coaxiality ≤0.02 mm

Material and Process
Main Body: PTFE (filled with 15% bronze powder), Elastomer: HNBR (hardness 75 Shore) A) Composite molding, surface roughness Ra≤0.8 μm, compression rebound rate≥70%, oil resistance conforms to ISO 6743-11 standard

Performance Parameters: Working pressure≤40 MPa, working temperature -30℃ to +120℃, linear velocity≤0.5 m/s, leakage ≤0.01 mL/min, chemical resistance compatible with hydraulic oil (SAE 10W–40), diesel, ethylene glycol, fatigue life≥6000 hours

Compatible Models: Cat C7.1/C9.3 industrial engines, 320D2/336D2 excavator hydraulic pumps (main pump/pilot pump), 950GC loader gearbox housing shaft bores, matching O-rings 257-2175, must be used in combination with O-rings during assembly (retaining ring + O-ring)

Installation and Maintenance Points: Clean the shaft surface and seat bore before installation. Shaft surface hardness ≥HRC58, roughness Ra≤0.8 μm, bore roundness ≤0.01 mm, free of burrs and rust; the retaining ring and O-ring are installed together, with the O-ring located inside the retaining ring (high-pressure side), and the compression controlled at 15%–20%.

Use a special tool (plastic/rubber material) to press in evenly, avoiding twisting or scratching the retaining ring. After installation, the end face runout of the retaining ring should be ≤0.03 mm, with no interference with the O-ring.

The working medium is Cat DEO-ULS 15W-40 machine oil or Cat HYDO Advanced 10 hydraulic oil. Avoid contact with strong acids and alkalis to prevent material aging.

Check the sealing condition every 2000 hours. If leakage exceeds the standard (>0.1 mL/min) or the retaining ring surface wear (>0.2 mm), both the retaining ring and O-ring must be replaced simultaneously to prevent seal failure.