PIN AS 2136710 - Caterpillar

793 (3SJ),
793B (1HL) Trucks;
994 (9YF) Loaders;
3508 (1ZF),
3512 (3YF),
3516 (4XF),
3516 (5SJ) Generator Set Engines;
3516 (4MJ),
3516 (5MJ) Marine EnginesSUPPLEMENT: 01/10/94Service Magazine; November 22, 1993; Page 15Disregard the Supplement to the Service Magazine; March 22, 1993; Page 7; "New Piston And Rod Group Has Lower Top Ring Position And Improved Ring Groove Cooling" article.
--------------- END SUPPLEMENT ---------------SUPPLEMENT: 01/10/94Service Magazine; March 22, 1993; Page 7; "New Piston And Rod Group Has Lower Top Ring Position And Improved Ring Groove Cooling". The Notein this article is NOT correct. The correct Note follows:
Caterpillar Diesel Engine Oil (CF-4) or premium engine oil with API CF-4 or API CF-4/SG specifications should be used. Both "CE" and "CD" specification oil is NOT acceptable for use with these pistons.--------------- END SUPPLEMENT ---------------SUPPLEMENT: 11/22/93Service Magazine; March 22, 1993; Page 7; "New Piston And Rod Group Has Lower Top Ring Position And Improved Ring Groove Cooling". Caterpillar Diesel Engine Oil (CF-4) or premium engine oil with API CF-4 or API CF-4/SG specifications should be used. Both "CE" and "CD" specification oil is NOT acceptable for use with these pistons.
--------------- END SUPPLEMENT ---------------Description of Change: A new piston and rod group is used in these machines and engines. The new piston and rod group include an improved two piece piston assembly. The improved piston assembly includes a new piston crown assembly and anew piston skirt. The new crown assembly has a 6.0 mm (.24 in) lower top ring location [19.3 mm (.76 in) verses 13.3 mm (.52 in) below top of piston crown] and a redesigned oil gallery. These changes will improve ring groove cooling. This will help reduce carbon build up in the ring grooves. Carbon build up in ring grooves can result in piston seizure or piston scuffing. Caterpillar Diesel Engine Oil (CF-4) or premium engine oil with API CE or CF-4 specifications should be used! These oils will help reduce the tendency for carbon build up in the ring grooves. "CD" specification oil is NOT acceptable for use with these pistons.Adaptable To: The new 6I2861 Rod And Piston Group is a direct replacement for the former 6I3017 and 7E1038 Rod And Piston Groups. The new piston and rod group are in effect as listed in Chart A. The new 6I2862 Crown Assembly and 6I2863 Skirt can be used as a direct replacement for the earlier crown assemblies and skirts as shown in Chart B. If a new crown assembly and skirt are installed in an engine in place of a former 7C6146 Crown Assembly and 7C6145 Skirt (part of the former 7C8121 Rod And Piston Group), the former 7C3710 Oil Cooling Jet Assembly must be re- placed with a new 7E4069 Oil Cooling Jet Assembly.The new 6I2861 Rod And Piston Group is included in the 0R3791 Cylinder Pack.