1994/01/01 Caterpillar

Cylinder Head Gaskets Improved To Provide Better Fire Ring Retention{1124}

Usage:

3406C, 3406E And 3408 Truck Engines

Reference: Truck Engine News, November 1992, Page 2, "New Cylinder Head Gasket, Spacer Plate and Head Bolts Used; New Cylinder Liner Projection Measurement Method; New Cylinder Head Torque Sequence".

The flexibility of the cylinder head gaskets created the possibility of disengagement of the fire ring and wrap from the body of the gasket during handling. If a head gasket is installed without a fire ring and wrap, the head gasket will fail.

The design of the cylinder head gasket has been changed. The number of tabs that secure the fire ring and wrap to the gasket body has been increased from four per side to six per side. The additional tabs will help prevent accidental fire ring and wrap loss during handling. The part numbers of the improved cylinder head gaskets have not changed. The improved cylinder head gaskets are in effect as shown in the Chart.

Caterpillar Information System:

1994/01/01 Possible Interference Problem With 9U-7241 Valve Spring Compressor Group{0703}

1994/01/01 Exhaust Valve Bridge Should Not Be Adjusted{1119}

1994/01/01 Cold Weather Operation{0374}

1994/01/01 New Valve Cover Gasket Used{1107}

1993/12/01 Uses, Characteristics, And Removal of Castrol Tarp®, Tarp-B®, And 4164®{0374}

1993/12/01 Procedure To Prevent Moisture From Collecting In The Hose Between The Air Inlet Manifold And Transducer Module (Boost Sensor){1917}

1993/12/01 Clarify Usage Of Parts Service Cylinder Head Gaskets{1124}

1993/12/01 Replacement Of Earlier Truck Engines In General Motors Topkick And Kodiak Trucks{1000}

1993/12/01 New Control Assemblies Used In Fuel Injection Control Groups{1298}

1993/11/01 8T-8697 Electronic Control Analyzer Programmer (ECAP) Improved

1993/11/01 New Dynamic Fuel Ratio Control (FRC) Settings Provide Improved Engine Response

1993/11/01 Low Power Complaints Caused By 9X7793 Rack Sensor Non-Linearity On Electronic Engines

1994/01/01 Flywheel Housing to Cylinder Block Joint Improvements{1157,1201}

1994/01/01 New Piston Body Has Improved Bonding Between Iron Band And Aluminum Body{1214}

1994/01/01 Fuel Injection Pump Improvements{1251}

1994/01/01 New Pedal Mounted Throttle Position Sensor Available{1913}

1994/01/01 List of Service Publications{0374}

1994/02/01 New Turbocharger Models Have Left-Hand Threads On Compressor Nut And Turbine Shaft{1053,1052}

1994/02/01 Remove Internal Components From 4P-8454 Cover Assembly{1309}

1994/02/01 September 1993 Personality Module Release Improvements{1902}

1994/02/01 New 7X-1715 Cable Assembly (Small, 40 Pin Breakout) Available{0779,1900}

1994/03/01 New Seal Used In Air Lines Group{1058}

1994/03/01 Improved 1R-0712 Fuel Filter Available{1261}

1994/03/01 Improved Ceramic Turbocharger Group Used{1052}