1978/03/13 Caterpillar

Soft Washers And Lockwashers Are Now Used With The Mounting Bolts For Air-Fuel Ratio Control{1278,1264}

Usage:

3406 and 3408 Vehicular, Industrial and Truck Engines;
3408 and 3412 Marine Engines (70V, 90U, 92U, 48W, 67U, 28V, 99U, 60M)

Description of Change: Soft washers and lockwashers are now used with the mounting bolts for the air-fuel ratio control on the above engines. The change was made to prevent contact between the mounting bolt and the shut-off shaft and still have enough threads for the bolt to engage correctly. Also, another change was made in 3406 Engines: The same mounting bolt that is used on 3408 and 3412 Engines is now used on 3406 Engines to give enough thread contact when the bolt is tightened. The bolt used formerly on 3406 Engines was shorter, and when the bolt was tightened it was possible for the threads to become damaged because very few threads were engaged.

Adaptable To: These changes are adaptable to all 3406, 3408, and 3412 Engines that have the air-fuel ratio control installed on the governor. These changes are not adaptable to 3408 and 3412 Engines that have the air-fuel ratio control installed on the fuel injection pump housing. The new parts are shown in the chart that follows:

Caterpillar Information System:

1978/03/13 When A 6N5906 Hour Meter Will Not Operate Correctly, Check The Electrical Supply Before A Replacement Hour Meter Is Installed{7480,1400}

1978/03/13 5P8687 Tee Test Tooling Group{0651,5050}

1978/03/06 New Starter Motors Have Solenoid On Top Of Starter{1407,1453}

1978/03/06 Use Again Specifications For Valve Springs Are Changed{1108}

1978/03/06 5P8558 Pressure Gauge Calibrating Group Checks Pressure Gauges{0650}

1978/03/06 Stronger Piston And Connecting Rod Are Tapered In Area Of Piston Pin{1213,1214,1218}

1978/02/27 New Tachometer Drive Adapter Assembly Prevents Failure Of The Seals For the Tachometer Drive Group And Transfer Pump{7462,1256}

1978/02/27 Modification Of Oil Pan For Installation Of Oil Sump Heater{1302}

1978/02/27 Improved Fuel Priming Pump Assembly Has Better Sealing Characteristics; Repair Kit Available For Knob{1258}

1978/02/27 Stronger Exhaust Manifold Gasket Now Used{1059}

1978/02/27 Replacement Seals And Wear Sleeves Now Available As A Crankshaft Seal Kit{1202,1160,1161}

1978/02/27 Fabricated Adapters Permit Horizontal Mounting Of Transmissions On 1P2420 Transmission Repair Stand{0640}

1978/03/13 The Causes And Reduction Of White Exhaust Smoke During Cold Engine Starts; Maintenance Aids Available To Decrease This Problem{1250,1383,1050}

1978/03/20 "Danger Do Not Operate" Tags Now Available{0374}

1978/03/27 Use 5P8706 Die Repair Kit For The Repair Of 9S6331 Die Assembly{0623}

1978/03/27 5P8675 Extension Handle Available For General Uses{0614}

1978/03/27 Improved Thrust Washers Now Used With Planet Gears{3000,3072,3106,3110,3003,3001,3100,3116,3159,3176,3107,5150,5165}

1978/03/27 9N3700 Or 9N3299 Nozzle Assemblies Must Be Used On 3208 Engines That Are Equipped With Exhaust Gas Recirculation (EGR){1254}

1978/03/27 How To Find Correct Oil Change Intervals For Truck Engines Operated In Short Distance Applications (Pick Up And Delivery Service){1318,7500,0374}

1978/03/27 5P4149 Conversion Group To Become A Discontinued Item On October 1, 1978{0650,1254}

1978/03/27 More Torque Now Used To Tighten The Retainer Nut For Turbocharger Compressor{1052,1053}

1978/03/27 Correct Adjustment Of The Governor Control Linkage In Truck Engines Is Necessary To Prevent Low Power{1265,1269}

1978/04/03 Procedure For Alignment Of Transmission Mounting Parts On 1100 Series And 3208 Truck Engines With Allison MT640, MT650, And AT540 Series Transmissions{3000,1156,1157}

1978/04/03 A Gasket Group Is Available To Give Improved Sealing For The Oil Supply To The Rocker Arms On Early Engines{1101,1102,1221}