1981/02/23 Caterpillar

Do Not Adjust The Fuel Setting Or High Idle Higher Than Necessary{1257}

Usage:

All On-Highway Truck Engines

The specifications for the fuel setting and high idle are given in Fuel Setting Information. These specifications have a tolerance that is also given in the Fuel Setting Information book or microfiche.

Some servicemen make adjustments to the high side of the tolerance, even when it is not necessary. For example, the static fuel setting specifications have a tolerance of ± .15 mm (± .005"). For a specification of 3.05 mm (.120"), the adjustment would be correct from 2.90 mm (.115") to 3.20 mm (.125").

It is important to remember that adjustments to the high side of the tolerances can cause a reduction in fuel mileage [km/L(mpg)]. On some engines this reduction can be as much as 0.09 to 0.13 km/L or .2 to .3 mpg. This will not be acceptable to many customers, especially those who have economy series engines.

Caterpillar Information System:

1981/02/23 Two New Oil Filter Assemblies Available; Always Use Correct Oil Filter And Follow Caterpillar Change Intervals{1318}

1981/02/23 Later Pistons Have A Smaller Number Of Drain Holes In Oil Ring Groove{1214,1213}

1981/02/23 New Governor Spring Available For Specific Engine Applications{1264,1265}

1981/02/16 Different O-Ring Seal Now Used On The Oil Pump Suction Tube{1307,1304}

1981/02/16 New O-Ring Seal Used In EGR (Exhaust Gas Recirculation) Control Has Better Resistance To Heat Damage{1080}

1981/02/16 New Publication: Engine Bearings And Crankshafts{0374}

1981/02/02 New Camshaft Has Improved Profile (Shape) Of Exhaust Cam To Extend Service Life{1210}

1981/02/02 Elbow With Orifice Now Used In Regulator And Housing Groups For Cooling Systems{1355,1361}

1981/02/02 Aluminum Identification Plate No Longer Used On Torque Converters; Identification Numbers Put Directly On Converter Housing{3101}

1981/02/02 Corrected "5.4" 60°V Main Bearing Selection Guide" Is Now Available{0374,1203,1202}

1981/02/02 New, One-Piece Valve Lifter Used{1209}

1981/02/02 New Exhaust Manifold Has Slip-Joint Connections{1059,1061}

1981/02/23 6V4163 Bit And 6V4164 Driver Now Available For Removal Of Bolts For Flyweight Carrier{0612,1264}

1981/02/23 Pipe Plug Added To Rear Of Cylinder Block Prevents Oil Leakage Into Flywheel Housing{1201}

1981/02/23 Changes Made To Power Cord Plugs On 5P6532 And 5P6533 Reader Projectors{0160}

1981/03/02 Changes Have Been Made To Some Caterpillar Service Publications{0375}

1981/03/02 High Concentration Of Aluminum In Oil Analysis Can Be The Result Of Rocker Arm Support Wear{1318,1102}

1981/03/02 Two New Exhaust Manifolds Available For Replacement Of Single Rear Manifold To Prevent Broken Studs{1059}

1981/03/02 Modification Of Flywheel Prevents Loose Clutch Pilot Bearing{1155,1156}

1981/03/02 Check Oil Level Carefully To Prevent Operation With Too Much Oil In Engine Crankcase{1316}

1981/03/09 Correct Preparation Is Important To Prevent Damage During Extended Periods Of Storage{7500}

1981/03/09 New Poppet Valves And Piston Available As Replacement Parts; Automatic Center Punch Can Be Used To Install Piston{3012,0622,0626,3166,3185}

1981/03/09 Test Procedure For Exciter Reactors On SRSE Generators{4454}

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