1980/11/24 Caterpillar

New Gasket Improves Operation Of Shut-Off Groups{7418,7403}

Usage:

D379, D398, D399 Industrial Engines

Description of Change: A new gasket is used in shut-off groups for D379, D398, and D399 Industrial Engines. The new gasket has separate openings for the rack cylinder passage and the oil drain passage next to it. This will make sure the rack cylinder circuit has the correct pressure for operation in all conditions. The former gasket had a single opening for these two passages, which were both drain passages on early shut-off groups. The single opening permitted an internal (inside) bypass where leakage of pressure oil in some conditions lowered the pressure in the rack cylinder circuit. This had an effect on rack cylinder operation only during an overspeed or manual emergency shut down. The cylinder operated correctly during a shut down caused by high coolant temperature or loss of engine oil pressure.

Adaptable As: The new 5N8227 Gasket is a direct replacement for the former 5N3199 Gasket, which is canceled.

Caterpillar Information System:

1980/11/24 Use Fluid-Type Vibration Damper To Control Vibrations{1205,3305}

1980/11/24 New Aftercooler Core Has Copper-Nickel Tubes For Increased Strength{1063,1064}

1980/11/24 New Decals Permit Easier Identification Of Fuel System Settings On Most Truck Engines{7557}

1980/11/17 Some Remanufactured 3406 Engines Have The Wrong Reference Serial Number On The Identification Plate{7557,1000}

1980/11/17 Use Dust Cap To Prevent Freon Leakage From Air Conditioner; Cap Is Available As Replacement Part{7320}

1980/11/17 Tee-Test Plug And Pressure Tap (Connection) Plugs Can Be Tightened To A Higher Torque To Prevent Leaks{5050,0651}

1980/11/17 6V4021 Piston Ring Compressor Group Available{1215,1214,0622}

1980/11/17 Two Thinner Spacers Available For Use During Adjustment Of Off-Engine Timing Dimension{1251,0653}

1980/11/17 Coolant Conditioner Elements Are Now Available For 3208 Engines{1350}

1980/11/17 Check For Correct Spring Retainer On Oil Pump Bypass Valve When Oil Pan Is Removed{1315,1302}

1980/11/17 Improved Cable Assembly For Mechanical Shut-Off Group{7418}

1980/11/10 6V3147 Main Bearing Wrench Now Available{1203,0612}

1980/11/24 6V4008 Valve Seat Extractor Now Available{1103,0622}

1980/11/24 Replacement Wheel Available For Service Of 6V97 Engine Stand Group{0626}

1980/12/01 Direct Inquiry Service Information Retrieval System (SIRS) Available To U.S. And Canadian Dealers{0374}

1980/12/01 Exhaust Manifold And Air Lines Groups Changed To Prevent Exhaust Leakage And Damage To Manifold Gaskets And Mounting Studs{1059,1061}

1980/12/01 Larger Plug Used In The Ends Of The Rocker Arm Shaft Assembly{1102}

1980/12/01 New Service Handle Kit Permits Cab Door To Be Opened From Inside While Locked (Fastened With Lock){7308,7301}

1980/12/01 New Front Housing Assembly And Gaskets Used{1162,1166,1151}

1980/12/01 Different O-Ring Seal Now Used On The Oil Pump Suction Tube{1307,1304}

1980/12/01 Inspect All Engine Oil And Fuel Filter Elements Before Installation{1000,1261,1318}

1980/12/01 6V4085 Torque Multiplier Group Available{0614}

1980/12/15 New Bearing Sizes And Identification Codes For AiResearch Remanufactured Turbocharger Cartridges{1053}

1980/12/15 Be Sure To Cut The Center Gasket Even With Top Surface Of Oil Pan Sections To Prevent Oil Leakage{1302}