1991/05/20 Caterpillar

New Speed Setting Clutch Group For 3161 Woodward Governors{1265}

Usage:

3500, 3600 Industrial And Generator Set Engines

Reference: This change applies to Code 118.03 in the 3600 Sales Manual.

Description of Change: A new speed setting clutch group is used on the 3161 Woodward Governor. The new clutch group incorporates a design improvement to the friction adjusting screw. Screw (1) on the former clutch group has been replaced with stud (5) that is brazed to manual speed adjusting gear (4). Screw (1) could come loose and cause excessive slippage between friction drive case (2) and the speed adjusting gear. Stud (5) prevents this slippage and maintains the required 1.4 to 1.7 N·m (12 to 15 lb in) slip torque between drive case (3) and speed adjusting gear (4).

Adaptable To: The new 9Y9685 Clutch Group is a direct replacement for the former 7C9523 Clutch Group and is adaptable to first production.

Illustration 1. Former 7C9523 Clutch Group.

Illustration 2. New 9Y9685 Clutch Group.

Caterpillar Information System:

1991/05/20 Two Scavenge Screens Now Used In Scavenge Oil Pumps{1312}

1991/05/20 Replace Camshaft And Install New Lifters If Pitting, Spalling, Or Wear Occurs On Lobes Of 4N0599 And 4N0602 Camshafts In Fuel Injection Pump Groups{1251,1253}

1991/05/20 Procedure To Retain Oil Pump When Pump Mounting Pad On Cylinder Block Is Broken{1201,1304}

1991/05/20 Cylinder Kits Not Recommended For Use In 3400 Family of Marine Engines And D8N Tractors{1214}

1991/05/20 Do Not Weld Repair Worn Wheel Spindles For Off-Highway Trucks Or Wheel Tractor-Scrapers{4002,4205,4234}

1991/05/13 Unwanted Engine Shutdown Caused By "01" And/Or "04" Diagnostic; New "09" Diagnostic Available With 8T9881-8 Electronic Control Module (ECM){4490}

1991/05/13 Engine Updates Help Prevent Piston Seizures{1214,1252,1265,1274,1355,1383,1393,1456}

1991/05/13 Rear Gear (Cam Drive) Groups Improved{1206,1201,1212,7551,7552,7553}

1991/05/13 New Specification For Exhaust Valve Clearance{1123,1121,1105}

1991/05/13 Replacing A 3176...(2YG) Truck Engine With A 1991 3176...(7LG) Truck Engine{1000,1119,1408,1901}

1991/05/13 Component Changes For 1991 Model 3176 (7LGH, 43Z) Engines{1052,1087,1119,1215,1290,1292,1304,1361,1362,1378,1408,1901,1902,1912}

1991/05/13 Larger O-ring Seal Available For Oil Supply Port In Governor Housing{1264}

1991/05/20 Correct Testing of Sensing Switches{7400,7402,7422}

1991/05/27 Expected Future Air Conditioning Service Requirements{7320,1802}

1991/05/27 Technical Marketing Information (TMI) System for Commercial Engine Products{0337,0334,0336}

1991/05/27 Smaller Connecting Rod Bolt Used In 4W6425 Air Compressor; Use Correct Torque{1803}

1991/05/27 New Fuel Manifolds And Clamps Reduce Vibration Of Fuel Lines{1252,1702}

1991/06/03 New Deutsch HD-10® Electrical Connectors Used{1400,1408}

1991/06/03 Reference Emissions Graph Helps Determine Oxides Of Nitrogen{1050}

1991/06/03 New Oil Drain Assembly Used; Be Sure To Correctly Tighten Drain Plugs, Port Plugs, And Pipe Plugs In Oil Pans{1302}

1991/06/10 New Timing Specifications For 3500 Spark-Ignited Engines{1552}

1991/06/10 1,1,1-Trichloroethane May Damage Deutsch C-E Electrical Connectors{1400,0645,0785,1450,1550,1900,3168,3225,3418,4294,4323,4450,5485,5700,7400,7450}

1991/06/17 New Three-Ring Pistons And New Rings Used In New Piston And Rod Groups To Provide Improved Oil Control{1214,1215}

1991/06/17 New Seal And Improved Plate Eliminate Leaks In BrakeSaver Water Lines Group{1380,1155}