BEARING AS-ROLLER 1283935 - Caterpillar

Engines:
G3500 SeriesDescription of Change: A new valve stem seal is used in the cylinder head groups for all landfill applications. This new valve stem seal helps control the amount of oil that flows down the valve stem into the combustion chamber. This will help reduce deposits in the combustion chamber. The deposits are the result of oil additives that mix with Siloxanes during the combustion of landfill gas. The reduction of deposits in the combustion chamber will help to reduce guttering of valves in most landfill applications.The new valve guides are used in all of the cylinder head groups. The top of the new valve guides have a short length of reduced outside diameter. This area of reduced outside diameter allows clearance for the installation of the new valve stem seal.Adaptable To: The new 137-6856 Seal (Valve Stem) is used in the cylinder head groups in all landfill applications. See the tables that follow for the applicable cylinder head group part numbers.Note: The new 137-6856 Seal (Valve Stem) is intended for use in landfill applications only. Caterpillar recommends the 0R-8082 Cylinder Head Group and the 0R-7734 Cylinder Head Group for use in landfill applications only.The new 184-5495 Valve Guide (Intake) is a direct replacement for the former 9Y-6883 Valve Guide (Intake). This new intake valve guide has two grooves around the outside diameter. These grooves are located just below the area of reduced diameter that is on the top of the valve guide. The former valve guide is cancelled.The new 184-5494 Valve Guide (Exhaust) is a direct replacement for the former 9Y-6882 Valve Guide (Exhaust). This new exhaust valve guide has a groove around the outside diameter. This groove is located just below the area of reduced diameter that is on the top of the valve guide. The former valve guide is cancelled.The inside diameter of the new intake valve guide and the new exhaust valve guide are not finished prior to assembly. The inside diameter of both of the new valve guides must be reamed to the final specifications after the valve guides are installed in the cylinder head. See Specifications, SENR6411-02, "G3500Engines", "Valves". The tables that follow identify the cylinder head groups that include the new valve guides.
Table 1
Cylinder Head Component Reference For G3500 Series Engines In Landfill Applications    
Component    Landfill
(Quiescent)    Landfill
(Swirl)    
Reference Top Level
Cylinder Head Groups (1)     185-3507     184-4976    
Type Of Exhaust Manifold     Wet Manifold     Dry Manifold    
Basic Cylinder Head Group (2)     123-8650 CRB 144-6410     184-5497    
Remanufactured
Basic Cylinder Head Group (2)     0R-8082 CRB 0R-7734     0R-7739    
Upgrade-To-New
Basic Cylinder Head Group (2)     0R-8081 CRB 0R-7735     0R-7740    
Valve Seat Inserts (Intake)     6I-1713
110-7726 (0.127 mm OS)
110-7727 (0.254 mm OS)     122-5963
158-8036 (0.127 mm OS)
158-8037 (0.254 mm OS)    
Valve Seat Inserts (Exhaust)     6I-1713
110-7726 (0.127 mm OS)
110-7727 (0.254 mm OS)    
Valves (Intake and Exhaust)     104-7184    
Rotocoil Assembly     133-3814    
Valve Guides (Intake)     9Y-6883