STRAINER 2809503 - Caterpillar

When the cylinder head is reconditioned, inspect the seat for the precombustion chamber or D. I. adapter. If the seat is pitted or damaged, make a repair; see the instructions that follow. (1) Install the correct FT1766 Pilot Adapter (1) in hole (2), until the top of the pilot adapter is 5.0 (.2") below the seat surface. (2) Install 9.525Ø (.375"Ø) pilot (3) in adapter (1). Use a flat bottom grind stone (4) and holder (5), with a high speed driver, to remove pitting or damage from the seat surface. Remove as little material as possible, to keep dimension (A) to a maximum. (3) Remove the flat stone and use a 45° stone (6) to grind a chamfer (B) to the original dimension.