COUPLING AS 1160500 - Caterpillar

Note: If the inside diameter of cylinder exceeds the limit, replace the cylinder block. Bore the cylinders in the cylinder-number sequence to prevent heat-induced distortion.Reboring cylinder
Illustration 25 g02225573
Dimension for (A) 14.0 mm (0.55 inch) (B) Direction at right angles to piston pin
Pistons are available in two sizes (0.250 mm (0.0098 inch) and 0.500 mm (0.0197 inch) oversizes). Select the piston size for all cylinders based on the largest cylinder bore that has been measured.
Measure the outside diameter of the piston that has been selected. The measuring position in the outside diameter is shown in the Illustration.
Calculate the boring dimensions based on the piston outside diameter that has been measured.
3A:Piston outside diameter (mm) (oversize piston that has been selected)
3B:Clearance between piston and cylinder (standard) 0.030 mm (0.0012 inch)
3C:Honing allowance 0.040 mm (0.0016 inch) or below Boring dimension = 3A + 3B - 3C
Bore each cylinder to dimension calculated above.
Horn-finish each cylinder to achieve the final dimension (the piston outside diameter plus the clearance between the oversize piston and the cylinder bore.)Measuring crankcase top surface distortion
Note: Refacing of cylinder head should be kept to an absolute minimum. Excessive grinding of the cylinder head may result in defects such as defective combustion and stamping (contact between piston and valve).
Illustration 26 g02225649
Apply a straight edge to the top surface of the crankcase and measure crankcase distortion using a feeler gauge. If the distortion exceeds the limit, grind the cylinder head using a surface grinder.
Table 14
Item     Standard     Limit    
Distortion of crankcase top surface    
0.050 mm (0.0020 inch) or less    
0.200 mm (0.0079 inch)    Note: Do not over-grind the cylinder head, as the piston protrusion deviates from the standard value. Do not grind the surfaces more than 0.20 mm (0.008 inch) in total (cylinder head bottom surface plus crankcase top surface).Inspecting tappet
Illustration 27 g02225650
Contact surface of tappet and cam (18) Good (19) Bad (20) BadInspect the cam contact surface of the tappets. Fit new tappets if the surface is excessively worn or damaged.Measuring clearance between tappet and tappet guide hole
Illustration 28 g02225653
Measuring tappet outside diameter and crankcase tappet bore inside diameter (AC) Measuring direction (AD) Measuring pointsMeasure clearance between the tappet and tappet hole. Replace the tappet with a new one if the limit is exceeded.
Table 15
Item     Nominal Diameter     Standard     Limit    
Tappet hole inside diameter    
14.0 mm (0.55 inch)    
14.000 to 14.018 mm (0.5512 to 0.5519 inch)    
14.100 mm (0.5551 inch)    
Clearance between tappet and tappet hole     -    
0.016 to 0.052 mm (0.0006 to 0.0020 inch)    
0.080 mm (0.0031 inch)    Inspecting piston cooling nozzle
Illustration 29 g02225654
Inspecting piston cooling nozzleInsert the round bar (21) (diameter 4.000 mm (0.1575 inch) or less) to the top of the piston cooling nozzle installed on the crankcase. Inspect that the steal ball operates smoothly. If piston cooling nozzle is not worked smoothly, replace the piston cooling nozzle with new one.