IDLER GP-FRONT 2487150 - Caterpillar

Procedure To Update Former Carrier To Use Pin Lock Bearing
Before drilling the dowel hole in the carrier, check that the bearing diameter isn't worn down from the turning bearing. The 1T-1784 Carrier has a bearing diameter of 95.026 0.013 mm (3.7412 .0005 in) while the 1T-1908 Pin Lock Carrier has a bearing diameter of 95.016 0.013 mm (3.7408 .0005 in).
The bearing press fit does not have to be as tight with the pin lock bearing since the pin prevents rotation. However, the bearing diameter must meet the 95.016 0.013 mm (3.7408 .0005 in) specification as a minimum requirement.
There is no angular orientation for the dowel hole, but it would be best to stay away from the cored slot. See Illustrations 1 and 2 for hole size and depth.
Use a 1T-0796 Pin to retain the 8E-5248 Bearing as mentioned in "Reference Article".
Illustration 1. 1T-1908 Carrier-Stator Datum (A), Datum (B), Detail (C), See Note D below (D), 4.00 0.08 mm (.157 .003 in) (E).NOTE D: Select drill diameter size that will provide the proper amount of stock to be removed by the final sizing operation, but control the depth to 6.4 mm (.25 in) remaining in the completed part. Final sizing diameter of 6.248 0.025 mm (.2460 .0010 in) to a depth of 5.1 0.5 mm (.20 .02 in). No required relationship with any axis.
Illustration 2. Detail C See Note F below.NOTE F: Surface finish must be a maximum of 2.5 micrometers when checked with a chisel stylus whose maximum width is 1.60 mm (.063 in). This diameter must be held to within 0.08 mm (.003 in) runout when moved on datum A and rotated about B. Diameter is 95.016 0.013 mm (3.7408 .0005 in).