1981/10/05 Caterpillar

New Torque Specifications For Flared And O-Ring Fittings{5057,7553}

Usage:

SUPPLEMENT: 02/01/82

SERVICE MAGAZINE, OCTOBER 5, 1981, PAGE 4. In the article, "New Torque Specifications for Flared and O-ring Fittings," the torque specification for the 12.70 mm (.500") tube with a 3/4" thread size is not correct. The correct torque is 50 ± 5 N·m (35 ± 3 lb ft). Make a note of this change.

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

Some of the general torque specifications for flared and O-ring fittings have been changed. These general specifications are given in the front of the Specification Section of the Service Manual. A note of these specification changes can be made in your Service Manuals. The correct specifications are:

Also, under the title "Assembly Of Fittings With Straight Threads And O-Ring Seals" change Step 2 to read as follows:

2. To put the fitting assembly in its correct position, turn the fitting body (2) out (counterclockwise) a maximum of 359°. Tighten locknut (3) to the torque shown in the chart.

Caterpillar Information System:

1981/10/05 Hydraulic Cylinder Repair Stands And Kits Now Available From Caterpillar Parts Department{0623,0626}

1981/10/05 Service Manual Information About Inside Diameters Of Valve Guides{1104,0374}

1981/09/28 Wrong Assembly Or Adjustment Of Governor Linkage Can Cause Failure{1289,1264,1265}

1981/09/28 Oil Pan Drain Plug Has More Threads{1302}

1981/09/21 Lubricant Gives Protection To Camshaft And Roller During Initial Start-Up{1210,1209}

1981/09/21 Use Only EPA-Approved Rack And Idle Setting; Change Seal, Date Plate{1257,1251,1264}

1981/09/21 New Dual Speed Switch Is Now Available{7418,7410,7411,1400}

1981/09/21 Preventive Maintenance For Natural Gas Engine Spark Ignition System{1550,1552,1555,1558}

1981/09/14 Spring Pins No Longer Used In Water Pump Drive Gear {1361}

1981/09/14 Low Idle Instability: New Low Idle Setting {1264}

1981/09/14 Timing Pin Removed From Governor And Fuel Injection Pump Group; Change To Service Manuals {1286}

1981/09/14 Exhaust Manifold And Air Lines Changes Prevent Broken Studs And Exhaust Leaks {1059,1061}

1981/10/05 New Piston Ring Group For Parts Service In Natural Gas Applications{1215}

1981/10/05 Bolt Torque Specifications Changed For Crankshaft Pulley And Power Take-Off Adapter{1205,1165}

1981/10/12 New Cylinder Block Permits Use Of A Small-Frame Turbocharger{1201,1052}

1981/10/12 Use Of Engine Supports On Flywheel Housing Can Change Face And Bore Runout Measurements{1157}

1981/10/12 Engine Slobbering; New Piston And Rings Used{1214,1215,1000,1225,1104,1052}

1981/10/12 FT1561 Cylinder Liner Storage Cabinet{0632}

1981/10/19 FT1565 Valve Guide Removal And Installation Tool{0623,0624,1104}

1981/10/19 Use Shorter Lubrication Periods Under Severe Operating Conditions{7500}

1981/10/19 Wrong Fuel Setting Information Given In Microfiche{0374,1251,1264,1257}

1981/10/19 New Washers Make A Better Seal In Aftercooler Water Pumps{1363}

1981/10/19 Reference Chart For Major Production Changes On 3208 Engines{0374,0375,1000}

1981/10/26 Improved Head Gasket Has Larger Fire Ring To Decrease Fretting {1101,1201}