1981/03/23 Caterpillar

Correction To Torque Specification For Locknuts On Valve Clearance Adjustment Screws Of Engines Equipped With Jacobs Engine Brakes {1119,1102}

Usage:

3406 Truck Engines

Service information from The Jacobs Manufacturing Company has given a torque specification of 35 to 40 N.M (25 to 30 lb ft) to tighten the locknuts on the valve clearance adjustment screws. This torque is too high, and has caused damage to the adjustment screws on some engines.

To prevent this possible problem, a revision will be made to their service information as soon as possible. The later specifications will show a torque of 28 to 35 N·m (22 to 25 lb ft), which is within (inside) Caterpillar specifications for these engine models.

Make a note of this torque in any service information you have from The Jacobs Manufacturing Company. Be sure to use the correct torque during service work on engines equipped with the Jacobs Engine Brake.

Caterpillar Information System:

1981/03/23 Longer Cable Assembly Now Used In The 9S2000 Flowmeter {0651}

1981/03/23 Fuel Pressure Relief Valve Is Shown Inverted (Wrong End Up) In Parts Book Illustrations {1253,1286}

1981/03/23 6V4009 Dowel Driver Available {0622,1101}

1981/03/23 6V2029 Fixture Group Available For Adjustment Of Air/Fuel Ratio Control {0626,1278,0652}

1981/03/16 New Shield Assemblies Used In Water Shielded Manifold Group{1067}

1981/03/16 New Inlet And Exhaust Valves And Valve Guides Have Tighter Fit To Prevent Corrosion And Guide Wear{1104,1105,1101,1103,1108,1109}

1981/03/16 5P1075 And 5P1076 Washers Have A Different Design{7553,0680}

1981/03/16 Approximate Liquid (Refill) Capacities Added To Specifications Page In Parts Book{0374}

1981/03/09 Clean Electrical Contacts In Exhaust Gas Recirculation (E.G.R.) Switch Group And Cover Assembly Before Installation{1080}

1981/03/09 New Aftercooler Core has Improved Design To Prevent Vibration Damage Which Lets Coolant Into Engine Air Inlet{1064}

1981/03/09 Correct Installation Of Inserts Necessary During Repairs To Prevent More Counterbore Cracks{1217,1201}

1981/03/09 Special Studs And Nuts Available For Exhaust Manifolds On Engines Used In Heavy Load Conditions{1059,1101}

1981/03/23 New Tool Makes Glow Plug Wire Removal Easier {0622,0621,1403}

1981/03/30 Check All Settings When Fuel Injection Pump Group Is Installed{1286,1264,1251,1253}

1981/03/30 Low Engine Temperatures: Install Check Valve{1353,1355,1370,1380}

1981/03/30 6V3197 Spacer, 6V3041 Tool Group Available For Use During Removal and Installation Of Piston Pin Bearings{0622,1219,1218,1214}

1981/03/30 6V3150 Engine Pressure Group Gives Direct Indication Of Manifold Pressure{0651,1058}

1981/03/30 Electrical Information For EGR (Exhaust Gas Recirculation) Systems On 3208 Truck Engines So Equipped{1080}

1981/03/30 Brass Plug Now Used Instead Of Steel Plug In Sea Water Aftercooler{1063}

1981/04/06 Woodward Governor Available For Parallel Generator Applications{1289,1264}

1981/04/06 New Spacer And Plate Used In Transmission Lower Shaft Groups{3307}

1981/04/06 New Temperature Range Recommendation For Multi-Viscosity Oil In Power Shift Transmissions{3179,3155,3159}

1981/04/06 Use Heat-Indication Products To Measure Parts Temperatures{0651}

1981/04/06 Cooling System Cleaner Removes Rust And Corrosion{1350,1353,1354}