CYLINDER AS 3171449 - Caterpillar

3500, D343, G343, D348, G348, D349, G349, D353, G353, D398, G398, D399 And G399 Industrial and Natural Gas Engines Equipped With Twin Disc IBF Series Rear Power Takeoff ClutchesDescription of Change: Labyrinth-type seal rings are now available for use in the power takeoff groups on the above engines. With the use of these seal rings it will be possible to use grease as a lubricant for the main clutch bearings. The use of grease will increase the service life of the main clutch bearings. Originally these power takeoff clutches had lip-type seals and used oil as a lubricant for the main clutch bearings. Special Instruction, Form SMHS8189, gives instructions for the conversion of these clutches from oil to grease lubrication. This Special Instruction also gives information on how to make the labyrinth-type seal ring. This is no longer necessary because the seal rings are now available from the parts department.
Adaptable To: The new 2W4904 and 2W4905 Seal Rings (labyrinth-type) are adaptable to all the above engines. The 2W4904 Seal Ring can be used in 3N6545, 3N8613 and 3N8614 Clutch Assemblies. The 2W9405 Seal Ring can be used in 7L7490, 7L7759 and 3N8615 Clutch Assemblies. Special Instruction, Form SMHS8189, can still be used to make the conversion to the use of grease lubrication and for installation of these new labyrinth seals.