LOCKNUT 4329621 - Caterpillar

Table 1
Quantity New Part Number Description Old Part Number
12 390-8763 Piston Body As 367-5160
24 230-2569 Pin Retainer 250-2940The 390-8763 Piston Body As cannot be used in combination with the older style 247-7790 Piston Body As and the 10R-6009 Piston and Rod Gp on engines built with the 213-4835 Piston and Rod Gp. In order to use the new piston on the 213-4835 Piston and Rod Gp all 12 pistons must be replaced.The new 230-2569 Pin Retainer must be used when assembling the new pistons onto the piston rods. Note: Do not mix the piston types in this group.The new 390-8763 Piston Body As can be used in combination with the older style 335-6186 Piston Body As, the 361-3941 Piston Body As, the 367-5160 Piston Body As, and the 20R-0194 Cylinder Pack As on engines built with the 335-6188 Piston and Rod Gp and the 357-7154 Piston and Rod Gp.Note: The mixing of piston types is allowed in this group.The procedure outlined in Special Instruction, REHS5705, "Break-In Procedure for the 20R-0194 Cylinder Pack Assemblies Used in C32 Marine Engines" is recommended.The new pistons are adaptable back to first production on the above listed engines.The changes are effective at the factory with the engine serial numbers that are listed in Table 2.
Table 2
Effective Serial Numbers
S/N:RNC03199-UP
S/N:RNZ01142-UP
S/N:T3T00384-UP