SPRING 2474579 - Caterpillar

Engine:
3512B (S/N: PWG1-UP)
3516B (S/N: BCK1-UP)
Description of Change: A new piston and rod group with a one-piece piston has been introduced for the above engines. The new piston is forged steel of the monotherm design that is already used in standard displacement engines. A large circumferential slot separates the crown and the skirt. The crown and the skirt remain attached by the strut for the pin bore.Adaptable To: The new 341-3640 Piston and Rod Gp is a direct replacement for the 253-3066 Piston and Rod Gp in the above engines. The 253-3066 Piston and Rod Gp is not canceled.The new 341-3640 Piston and Rod Gp is adaptable to the above engines back to first production.The new pistons have the same balance weight as the previous pistons. The new pistons can be used in the same engine with the previous pistons. However, a new piston cooling jet and a retainer for the jet must be used with the new piston.
Failure to install the correct piston cooling jet and retainer will result in inadequate lubrication which will cause piston seizure and catastrophic engine damage. Install the correct piston cooling jet and the correct retainer.
The new 341-3640 Piston and Rod Gp includes the appropriate 204-5447 Piston Cooling Jet As and 204-5447 Piston Cooling Jet As. Make sure that the parts are installed with the new piston.
Illustration 1 g02830638
341-3640 Piston and Rod Gp (1) 204-5447 Piston Cooling Jet As (2) 193-3282 Retainer As
Illustration 2 g02830741
253-3066 Piston and Rod Gp The new piston and rod group is effective with the following serial numbers:
BCK00374
PWG00231