1998/04/27 Caterpillar

Orifice In Control Valve Prevents Sudden Stop Of Truck Body When Hoist Control Is Returned From Raise To Hold {5136}

Usage:

793C (4AR) Off-Highway Trucks

Description of Change: An orifice is now used in the return passage of the housing for hoist pilot oil, and is part of the control valve. The orifice restricts pilot oil returning from the end of the directional spool in the control valve when the directional spool is returning from the RAISE to the HOLD position. Restriction of pilot oil prevents a sudden stop of the truck body and improves control.

Adaptable To: 4J-9780 Orifice (2) is effective with Serial No. 102 on the 117-9542 Control Valve, and is adaptable to 117-9542 Control Valves, with earlier serial numbers, used on 793C (4AR) Off-Highway Trucks.

The 4J-9780 Orifice (2) is installed in the threaded hole in the 106-7375 Housing (1), which is part of the 117-9542 Control Valve.

117-9542 Control Valve

(1) 106-7375 Housing.

(2) 4J-9780 Orifice.

Caterpillar Information System:

1998/04/27 Flushing Procedure Assures Correct Operation Of Implement Control Valves {5051}

1998/04/20 Change Implemented To Reduce Rear Hopper 102-9849 Hinge Pin Failures{6639}

1998/04/20 1U-5551 Extension Valve Needed To Check Nitrogen Charge Pressure In Belt Tension Accumulators{4197,5077}

1998/04/20 New Improved Fuel Fill Cap For Asphalt Pavers{1273}

1998/04/20 Improved Rear Fender Kits Are Available{7252}

1998/04/20 Propel Motor Displacement Screw Settings{4351}

1998/04/20 New Decals Striping For Dump Bodies{7559,7581}

1998/04/20 Dash Cover Assembly Has Been Improved{7314}

1998/04/20 Additional Information For VIMS Brake Temperature Indicator{7489,7601,7450}

1998/04/20 Primary Pressure For Transmission Pressure Control Group Has Increased{3030,3074}

1998/04/20 Engine Software Updates{1902}

1998/04/20 Additional Field Assembly Information For Off-Highway Trucks{7960,7961}

1998/04/27 New Piston Pump For Brake, Steering, And Hoist Systems Has Longer Service Life {5070,4268,4306,5083}

1998/04/27 Effectivity Date For Caterpillar Extended Life Coolant In Machines Shipped From CPPI {1350,1395}

1998/04/27 Improved Material Deflector For Primary Conveyor Is Available {6621}

1998/04/27 New Lubrication And Maintenance Interval Decal, SEEU7039, Now Available {0374,0653,7000}

1998/04/27 Revised Walk-Around Inspection Chart, SELU7039-01, Now Available {0374,7000}

1998/04/27 Gear Box Dipstick Is Now A Plug {4350}

1998/04/27 New Improved Parking Brake Switch Has Heavy Duty Switch And Contacts {7451}

1998/04/27 Grade Controls-New Setup Screens {5645,7220}

1998/04/27 Ladder Clamps Added To Secure Conveyor Pump EDC Wires {5702}

1998/05/04 New Coolant Level Sensor And Harness Assembly Improves Ground Path{1377,7470}

1998/05/04 Procedure To Retrofit 1R-0762 "Radial Seal" Filter Assembly{1260,1262}

1998/05/04 Improved Final Drive Pinion Bearing Setting Procedure Used And New Shim Pack Kit Available{4050,4091}