2010/07/02 Introduction of One Piece Piston Cylinder Packs for 3500 High Displacement Engines {1214, 1239, 1331} Caterpillar

Machine Engines:

3500B and 3500C High Displacement

Service Magazine, SEPD1145, 2 July 2010, "Introduction of RemanufacturedOne Piece Piston Cylinder Packs for 3500 High Displacement Engines". The article has been revised to add two new Reman cylinder packs.

Description of Change: New cylinder packs have been introduced for 3500 High Displacement Engines. The cylinder packs contain a one-piece forged steel piston (monotherm piston). This design is currently used on the 3500 Engines with standard displacement. A large circumferential slot separates the crown and the skirt. The crown and the skirt remain attached by the strut for the pin bore.

Table 1 illustrates the old part numbers and new part numbers. Illustration 1 shows the affected parts.

Illustration 1	g01916033
Forged steel piston (1) Piston (2) Rod (3) Piston cooling jet

Adaptable To: The new pistons are a direct replacement for two-piece pistons which are currently used in 3500 High Displacement Engines. The new pistons have the same weight and balance as the previous pistons. The new pistons can be used in the same engine with the previous pistons. However, the following cylinder packs and pistons require the 204-5447 Piston Cooling Jet Assemblies and the 193-3282 Retainer Assemblies (Piston Cooling Jet). When you are ordering and replacing cylinder packs, the cooling jet and the retainer must also be ordered and installed.

• 10R-9224 Cylinder Pack As

• 20R-0582 Cylinder Pack As

• 331-9822 Piston

• 339-3027 Piston Assemblies

Table 1

Machine	Engine	Old			New
789C 793C 793D 994F	3516B HD	Reman Cylinder Pack	10R-4029		Reman Cylinder Pack	10R-9224 (1) (2) (3)
		Piston Crown	172-0919		Piston Assemblies	331-9822 (1) (2) (3)
		Piston Skirt	155-5271		Cooling Jet	204-5447 (2)
		Cooling Jet	162-3898		Cooling Jet Retainer	193-3282 (2)
		Cooling Jet Retainer	121-3558		Piston Pin	302-3451 (2)
		Piston Pin	138-8508		Piston Pin Retainer	253-1238 (2)
		Piston Pin Retainer	8N-7296
797 797B	3524B HD	Reman Cylinder Pack	10R-4029		Reman Cylinder Pack	10R-9224 (1) (2) (3)
		Piston Crown	172-0919		Piston Assemblies	331-9822 (1) (2) (3)
		Piston Skirt	155-5271		Cooling Jet	204-5447 (2)
		Cooling Jet	162-3898		Cooling Jet Retainer	193-3282 (2)
		Cooling Jet Retainer	121-3558		Piston Pin	302-3451 (2)
		Piston Pin	138-8508		Piston Pin Retainer	253-1238 (2)
		Piston Pin Retainer	8N-7296
785D	3512C HD	Reman Cylinder Pack	10R-9258		Reman Cylinder Pack	20R-0582
		Piston Crown	249-4512		Piston Assemblies	339-3027 (1) (2) (3)
		Piston Skirt	155-5271		Cooling Jet	204-5447 (2)
		Cooling Jet	162-3898		Cooling Jet Retainer	193-3282 (2)
		Cooling Jet Retainer	121-3558		Piston Pin	302-3451 (2)
		Piston Pin	138-8508		Piston Pin Retainer	253-1238 (2)
		Pin Retainer	8N-7296

( 1 )	Drilled rods must be used.
( 2 )	All parts in the new column must be used together. Mixing of two-piece piston parts with monotherm pistons will result in severe engine damage.
( 3 )	Monotherm pistons can be mixed in the same engine with two-piece pistons. However, be sure that the correct cooling jet and the retainer are used with each piston.

Show/hide table

NOTICE
Failure to install the correct piston cooling jet, the retainer, and the connecting rod will result in inadequate lubrication. Inadequate lubrication will cause piston seizure and catastrophic engine damage. Verify that the correct parts are installed.

Table 2

Effectivity One Piece Piston Cylinder Packs for 3500 High Displacement Engines
Sales Model	Serial Number
New Engines
785D	S/N:B7F00193
789C	S/N:8WM02262
793C
793D
994F
797	S/N:3TN00944
797B
Reman Engines
789C	S/N:MSX00261
793B	S/N:KNS00569
793C	S/N:CPW01116
793D	S/N:MSK00228
797 797B	S/N:CND00430 S/N:NPM00196 S/N:SKN00294 S/N:SPM00355
994F	S/N:KDK00208