1988/10/03 Caterpillar

Main Rotor Shaft Changed to Eliminate Loose Connecting Bolts {4457}

Usage:

SR 4 Generators With 580 And 680 Series Frame Numbers

Description of Change: The main rotor for SR 4 Generators with 580 and 680 Series frame numbers is modified to allow the exciter rotor to contact the shoulder of the main rotor shaft. The exciter rotor is assembled using small socket head bolts which do not contact the smaller diameter shoulder on the main rotor. This prevents loosening of the bolts that connect the exciter rotor and retainer plate to the main rotor. The former hex head bolts came in contact with the shoulder of the former rotor shaft and prevented a solid fit for the exciter rotor.

The illustration shows the changes that were made to the rotor shaft and the relative positions of the new bolts to the rotor shaft shoulder.

Comparison of former and new main rotor shafts.

Adaptable To: Chart A shows the beginning serial numbers for this change.

The former main rotors cannot be used on later generators without also replacing the exciter rotor. Also, the "hex bolt" exciter rotors are not compatible with the redesigned main rotors. Chart B contains a list of new part numbers available for the main rotors and exciter rotor heat sink assemblies. More rotor part numbers will be available later.

Caterpillar Information System:

1988/10/03 Check Valve Added To Keep Air From Entering Fuel System {1264}

1988/09/26 Multipurpose Storage And Handling Systems For Parts {1100,0660}

1988/09/26 New VR3 Regulator Has Improved Short Circuit Protection {4474}

1988/09/19 Caterpillar Introduces A "Hotline" For Medical Information On Hazardous Materials (U.S. And Canada){0353,0373}

1988/09/19 New Service Tools Available{0600}

1988/09/19 Bellows-Type Exhaust Seals Used On Water Cooled Turbochargers{1059,1070}

1988/09/19 New Heat Sinks Have Solid Diode Wires{4472}

1988/09/19 New Dipstick, Breather, And Oil Filler Cap Minimize Oil Leakage{3311,3354}

1988/09/05 Improved Air Cleaner Element Has Pleats That Are Evenly Spaced{1054}

1988/09/05 New Piston Cooling Jets Used{1331,1200}

1988/09/05 New Rocker Arm Shaft Assembly and Bolts Used{1102}

1988/08/29 New Exhaust Manifold System Used {1059}

1988/10/03 Tool Storage For Centurion Track Press Tools {4150,0660,0729}

1988/10/17 New Service Tools Available{0600}

1988/10/17 Self-Locking Bolts Used In Front Timing Gear Group{1206}

1988/10/17 New Woodward Actuator Assembly (EG10P) Has Lower Relief Valve Setting{1289}

1988/10/24 New Graphite Exhaust Manifold Gasket Replaces Stainless Steel Gasket{1059}

1988/10/24 New Flywheel Assemblies Used In With Rear PTO Arrangements{1156}

1988/10/24 Head Bolt Holes In Cylinder Blocks Can Be Repaired{1201,1101}

1988/10/24 Seal Retainer And Seals Are Required When A New Cylinder Head Assembly Is Installed{1100}

1988/10/31 New Fuel Shutoff Solenoid Assembly Used{1259}

1988/10/31 New Air Cleaner Group Has Improved Crankcase Fumes Disposal{1051,1054,1317}

1988/11/07 New Oil Pressure Sender Assembly Used{7455}

1988/11/07 Identification Of Surge Suppressors{4454,4466}