WIRING GP-CHASSIS 2757192 - Caterpillar

Machining Procedure
In order to machine the holes for the coolant passage, it is necessary to remove the cylinder heads, the piston and connecting rod, and the cylinder liners. Refer to Disassembly and Assembly. It is not necessary to remove the studs for the cylinder heads. If you are using a magnetic base drill, the center line of the drill spindle must be no more than 47.625 mm (1.875 inch) from the front surface of the drill or the cylinder head studs must be removed. The removal of the studs for the cylinder heads may help facilitate the drilling of the holes in some installations.Cylinder Blocks with Neither of the Holes Drilled for the Coolant Passage
Before you begin the machining process, lower the protective plug into the lower area of the cylinder liner bore of the cylinder block that is being machined. Use duct tape along the flange of the protective plug in order to help seal off the lower end of the bore for the cylinder liner. This will prevent large particles of debris from falling onto the crankshaft and into the oil sump. The mounting face for the cylinder head must be clean and free of scale and of dirt particles.
Lay out the location of the four holes that are drilled from the mounting face of the cylinder head. Refer to Illustrations 4 and 2.
Drill the holes on the mounting face of the cylinder head. Ensure that the drill bit is perpendicular with the mounting face of the cylinder head while you drill. All the holes that are drilled to a measured depth from the mounting face for the cylinder head 42.0 mm (1.654 inch). Refer to Illustration 2. While you drill the holes use the following drills in sequence. This will reduce the force that is required to drill.
9.525 mm (0.375 inch) two flute drill
12.70 mm (0.500 inch) four flute drill
19.05 mm (0.750 inch) four flute drill
22.0 mm (0.866 inch) four flute drill
Lay out the location of the four holes that are drilled from the side of the liner bore. Refer to Illustration 2. The holes will intersect with the holes that are drilled from the mounting face for the cylinder head.
Drill the holes on the side of the liner bore. Ensure that the drill bit is perpendicular with the side of the liner bore while you drill. All the holes that are drilled to a measured depth from the side of the liner bore 40.0 mm (1.575 inch). Refer to Illustration 2. Use the drills that were used in Step 3 in sequence.
Use a shop vacuum cleaner to remove any metal chips and dirt from the holes for the coolant passage, from the cylinder liner bore, and from the protective disc in the bottom of the cylinder bore. When the drilling of the holes for the coolant passage is complete, move to the next cylinder and repeat the procedure.Cylinder Blocks that have Existing Holes Drilled for the Coolant Passage from the Side of the Liner