1997/05/19 Caterpillar

Improved Crankcase Breather Group Is Available{1317}

Usage:

793 (3SJ),
793B (1HL520-Up) Off-Highway Trucks

Description of Change: An improved breather group is used in the current production of the above machines powered by 3516 (2PK1300-Up) Engines and (7CL278-Up) Reman Engines. The improved breather group has four breathers. The former breather group only had two breathers. During operation, engine pressure builds and some engine oil from the crankcase is mixed with the crankcase fumes. The crankcase breather group vents crankcase pressure and allows gaseous oil to separate into its liquid form and drain back into the engine.

High crankcase pressure causes increased flow rates through the breathers, preventing oil separation. The improved breather group with its four breathers allows more oil to be separated from the crankcase gasses and remain in the engine.

Adaptable To: The improved 124-5513 Breather Group replaces the former 101-0838 Breather Group in the above machine engines. The improved 124-5513 Breather Group is adaptable to first production, but an additional disposal tube group and hardware is needed. See the chart.

NOTE: Locate the improved breathers on number six and number eight cylinders.

NOTE: The improved 124-5513 Breather Group is not serviced as a group. Serviceable parts must be ordered separately. See the chart.

Caterpillar Information System:

1997/05/19 Improved Components For Air Lines Groups{1058,1063}

1997/05/19 New Engine Software Available For 3412E Engines In 24H Motor Graders{1920}

1997/05/12 New Cylinder Groups Use Piston For Internal Stop {7562,5101,5102,5104}

1997/05/12 Structural Improvement To Piston Permits Removal Of Piston Coatings {1214}

1997/05/12 Correction To 50 Hour Machine Lubrication Schedule {7521,6437,6451,6452}

1997/05/12 Dimensions To Produce Drive Shaft Sleeve {3253,3267}

1997/05/12 New Turbocharger Guard Now Used {1073}

1997/05/12 New Center Arms, Steering Arms And Lock Plates Used In Steering Linkage Groups To Improve Linkage Quality {4305,4300}

1997/05/12 Fabricated Rear Cross Tube Replaced With Casting To Improve Service Life {3268}

1997/05/12 New Engine Wiring Harnesses Allow Easier Engine Removal And Installation {1408}

1997/05/12 Improved Lever Assembly Allows Greater Clearance {5112,7117}

1997/05/12 Engine Support Tooling Available {3030,0701,0720,1001}

1997/05/19 Cylinder Rod For Suspension Cylinder Groups Has Larger Diameter Bolts For Piston Retention{7201}

1997/05/19 Improvements Made To Prevent Alternator Terminal Breakage{1405}

1997/05/19 Dimensions For Installing Attachment Tailgate Mounting Hardware On Articulated Truck Dump Bodies{7271,7258}

1997/05/19 Torques For Wheel Nuts And Bolts Are Incorrect In The Operation And Maintenance Manual{4201,4202}

1997/05/19 Installation Of Transmission Oil Distributor Sleeves{5208,3002,3159,3176}

1997/05/19 Improved Speed Sensor Group Used{1907}

1997/05/19 New Electronic Transmission Control Group Used{3032,3100}

1997/05/19 New Differential Pinion Bearing Setting Tool And Procedure Available{3258}

1997/05/19 Torque Specified For Piston Rod Nut In Steering Cylinder Group{4303}

1997/05/19 New Antirotation Bearing Pins And Bearing Lubrication Lines Used On Rear Suspension Cylinder Bearings To Increase Service Life{7218,7213,7201,7200}

1997/05/19 Backup Alarms Improved{7406}

1997/05/26 Foam Filled Oil Saver Tanks Used In Off-Highway Truck Rear Axle Groups To Increase Bearing Life{3260}