1979/09/03 Caterpillar

Important: Use Only 8N4029 Fan On 769C Trucks And 768C Tractors{1356}

Usage:

SUPPLEMENT: 11/12/79

SERVICE MAGAZINE, SEPTEMBER 3, 1979, PAGE 3. Some of the information in the article "Important: Use Only 8N4029 Fan On 769C Trucks And 768C Tractors", is not correct.

Some of the earlier machines originally had the steel, 6N449 Fans, but all of these fans were removed and the aluminum, 8N4029 Fans were installed.

Earlier parts books for the 769C Trucks and 768C Tractors list the steel, 6N449 Fan for parts service. This is not correct and this steel fan MUST NOT be used for parts service on 769C Trucks and 768C Tractors.

Because all of these machines are now equipped with aluminum fans, the last two sentences of the September 3, 1979 Service Magazine article are not correct. Put a mark through these sentences and make a reference to this supplement.

If replacement of a fan on a 769C Truck or a 768C Tractor becomes necessary, only the aluminum, 8N4029 Fan must be used for replacement.

--------------- END SUPPLEMENT ---------------

All 769C Trucks and 768C Tractors need to be equipped with the 8N4029 Fan. The new fan, made of aluminum, is a direct replacement for the original 6N449 Fan used on some earlier models. Lighter in weight than the former steel fan, the 8N4029 Fan puts less stress on the fan drive shaft. While older parts books still show the former fan and the NPR does not give a clear indication that only the 8N4029 Fan must be used, the conversion is very necessary. Check to make sure the correct fan is installed when 769 Trucks and/or 768C Tractors are available for service work.

Caterpillar Information System:

1979/09/03 Follow Recommendations Given In Special Instructions For Modification Of Rollover Protective Structures (ROPS) At All Times{7323,7325}

1979/09/03 Only One Dowel Pin Is Now Used To Hold The Thrust Bearing In The Correct Position{1053,1052}

1979/09/03 Use Caution To Prevent Damage To Plastic Check Valve In Hydraulic Oil Tank And Transmission Oil Tank Drain{5056,3177}

1979/08/27 New Design Thrust Plate Used In Crankshaft Group{1201,1202,1203}

1979/08/27 New Rocker Arms And Rocker Arm Shaft Have Improved Lubrication{1102}

1979/08/27 Engine Oil Viscosity Changed To SAE 10W/30 For Shipment From All U. S. Factories{1318}

1979/08/27 Hardened Washers And Increased Torque Are Now Used On The Bolts Which Fasten The Circle Drive Group To The Circle Drawbar{5207,6153}

1979/08/27 6V190 Clamp Is Available For Use On Sleeve Metering Fuel Systems{0626,1250}

1979/08/27 New Governor Housing Assembly Used In Governor And Fuel Injection Pump Group{1253,1264}

1979/08/27 Steering System Improvements Prevent Possible Damage To Steering Cylinder Sockets{4303,4304,4305,4322}

1979/08/27 New Seal For Precombustion Chamber Has More Resistance To Heat And Steam{1106}

1979/08/27 Why Engines Are Damaged By Fuel Sulfur{1104,1216,1280,1318,1215}

1979/09/03 Quick Disconnect Coupling On Optional Modification Of 5P4150 Nozzle Tester Permits Faster Exchange Of Adapters{0651,1254}

1979/09/03 Improved Wire Assembly For Glow Plugs{1403}

1979/09/03 Improved Hardware Now Used To Fasten Front Suspension Cylinder To Frame{7201}

1979/09/10 Insulation Sleeve For 5P7360 Tach Generator Now Available {7462}

1979/09/10 Stronger Bolt Now Used With Exhaust Manifold {1059,1307}

1979/09/10 6V2055 High Vacuum Grease Gives Better Oil Seal {1052,1053,1077,0682}

1979/09/10 Undercarriage Disassembly And Assembly Procedures And Specification Charts Are Available {4150,4159,4154,4171,4180}

1979/09/10 New Gasket Used In Water Lines Group For Aftercooler {1380,1063}

1979/09/10 Gasket Added To Rear Wheel Spindle Housing For A Better Seal {4205}

1979/09/10 Different Grease Fitting Now Used In Fan Drive Group {1359}

1979/09/10 Recommendation For Use Of A FLEX-HONE On 1100, 3100 and 3200 Series Engines {1201}

1979/09/10 Tee Handle Hexagonal Wrench In Rack Adjusting Tool Is Now Available For Parts Replacement