PUMP GP-PISTON 2573931 - Caterpillar

3400 Series Engines In All ApplicationsSUPPLEMENT: 05/00/90ENGINE NEWS; APRIL 7, 1982; PAGE 1; "Reconditioning Of Bridge Wear Seat Is Permitted; Will Prevent Bridge Replacement When Not Necessary."Disregard this article. Make reference to the article with the same title in this issue.
--------------- END SUPPLEMENT ---------------During engine reconditioning or when the rocker shaft assembly is removed, the serviceman must inspect the bridge wear seat to find if the bridge can be used again. Use a dial indicator to measure the amount of wear on bridge wear seats. Make sure the contact point on the dial indicator is small enough in diameter to get an accurate measurement. See Illustration 1 for typical wear.
Illustration 1. Typical wear on bridge wear seat.Use the bridge again if the wear is 0.13 mm (0.005") or less. See Illustration 2. When the wear seat is worn more than 0.13 mm (0.005") the worn surface of the seat can be ground flat. The maximum amount of material that can be removed is 0.38 mm (0.015"). If the seat can not be made flat, make a replacement of the bridge. Reconditioning of the wear seat can only be done once.
Illustration 2. Dimensions for reconditioning.