Detroit Diesel 71 Series Replaces 23502020. Bore Diameter: 4.250. Flange Outer Diameter: 4.771. Flange Width: 0.251. At Barrel: 4.6255. Sleeve Outer Diameter at Seal: N/A. We would love to answer every question, but we do run into very specific questions that should be directed to your mechanic. We sell parts and you or mechanic install […]