PLATE 2335165 - Caterpillar

3406 (11N) Engines In Caterpillar Machines, 3406(90U),
3406B (6TB) Industrial Engines, 3406B (4TB) Marine Engines, 3406B (2WB, 4RG, 4JK) Generator Set Engines, 3406 (4FD) Spark Ignited Engines, 3406B/C (3ZJ, 5KJ, 4CK) Truck EnginesSUPPLEMENT: 01/24/94Service Magazine; July 5, 1993; Page 9; "New Cast Iron Inlet Adapter And Impeller For Water Pumps".In the Reference section of the article, the Form Number of the Special Instruction is incorrectly given as SEHS9494. The CORRECT Form Number is SEHS9484.
--------------- END SUPPLEMENT ---------------Reference: "New Water Pump Groups Use Tapered Roller Bearing," in this issue.Service Magazine; August 31,1987; Page 11; "Recommendations For Preventing Cooling System Damage". Service Magazine; February 19,1990; Page 13; "Improvements Made To Water Pumps; New Groups/Parts Available For Certain Applications".
Service Magazine; November 23,1992; Page 5, "Supplemental Coolant Additive Requirements".
Reference: "Coolant And Your Engine," SEBD0970. Special Instruction, SEHS9494, "Using A 9Y3778 Water Pump Impeller with a 9Y5652 Inlet Adapter ".Description of Change: A new cast iron water pump adapter and impeller are being used. The mating profile of the new cast iron adapter and impeller have been changed to match the profile of the current aluminum adapter and non-metallic impeller. This change will permit complete interchangeability of these adapters and impellers.Adaptable To: The new cast iron 9Y3778 Impeller replaced the former 9Y5651 Impeller in the 4P2152 Basic Water Pump Group and its equivalent Remanufactured 0R2856 Water Pump Group before these pumps were replaced by the new 1025941 Basic Water Pump Group and its equivalent Remanufactured 0R3790 Water Pump Group. The 1025941 and 0R3790 Basic Water Pump Groups also use the new cast iron 9Y3778 Impeller. See the Reference Article "New Water Pump Groups Use Tapered Roller Bearing" in this issue. The new cast iron 4P2383 Adapter replaced the former 9Y5652 Adapter in the higher level 9Y5647 Water Pump Group at the same time the impeller was changed in the 4P2152 Basic Water Pump Group.
Location of the 4P2383 Adapter (1) and 9Y3778 Impeller (2).The new cast iron 4P2383 Adapter can be used with the former 9Y5651 Impeller. However, when using the former 9Y5652 Adapter with the new 9Y3778 Impeller in the 4P2152, 1025941, 0R2856 or 0R3790 Basic Water Pump Groups, the clearance between the adapter and the impeller MUST be checked. There is a possibility of interference due to the profile differences between the new 9Y3778 Impeller and the former 9Y5652 Adapter. See the Reference Special Instruction.
The former 9Y5652 Adapter is also not compatible with the non-metallic 7C5479 Impeller. See Reference Article Service Magazine; February 19,1990; Page 13; "Improvements Made To Water Pumps; New Groups/Parts Available For Certain Applications ".
Damage to other engine components, such as cylinder liner pitting, can be caused by coolant with no or a low concentration of coolant conditioner. See the Reference Caterpillar publication "Coolant and Your Engine," SEBD0970. Also, see the Reference Articles Service Magazine; August 31,1987; Page 11; "Recommendations For Preventing Cooling System Damage" and Service Magazine; November 23,1992; Page 5, "Supplemental Coolant Additive Requirements".