1978/04/24 Caterpillar

Oil Grooves And Harder Gears Are Now Used In The Oil Pumps On 6.25" Bore Vee Engines{1304}

Usage:

D379, D398, D399, G379, G398, G399 Engines

SUPPLEMENT: 01/08/79

SERVICE MAGAZINE, APRIL 24, 1978, PAGES 6 AND 7. In the article "Oil Grooves And Harder Gears Are Now Used In The Oil Pumps On 6.25" Bore Vee Engines", the 3N7701 and 3N7706 part numbers in the "New Part No." and "Former Part No." columns of the chart on Page 7 are wrong. Change 3N7701 to 3N7710 and 3N7706 to 3N7707.

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

Description of Change: The pump housing cover and inlet manifold assembly for oil pumps on the above engines now have oil grooves machined in them for better lubrication of the idler gear bearings. Also, a harder oil pump drive gear and idler gear is used in oil pumps on D399 and G399 Engines only.

When oil pumps for D399 and G399 Engines are rebuilt, pump housing covers and inlet manifold with oil grooves must be used to prevent a possible seizure of the oil pump. The pump housing cover and inlet manifold with oil grooves can be used when an oil pump is rebuilt for D379, G379, D398 and G398 Engines, but is not necessary.

Adaptable As: Direct replacement as shown in the chart.

Caterpillar Information System:

1978/04/24 Do Not Use The 5B1401 Cleaning Tool Group To Clean The Orifice In Capsule-Type Fuel Injection Nozzles{0650,1254}

1978/04/24 Use 6V100 Tool Arrangement To Remove And Install Piston Pin Bearings For Both Tapered And Standard Connecting Rods{0620,1218}

1978/04/17 Improved Oil Suction Tube Assembly {3300,3302}

1978/04/17 Locating Bushings For The 5P3550 Rod Boring Machine Will Now Hold Tapered Piston Pin Bushings {0626}

1978/04/17 Improved Yokes, Hardened Washers And More Torque Keep Valve Lifter Guides Tight {1209}

1978/04/10 New Lifting Eye Group Used On 3412 Industrial Engines Equipped With Turbochargers{1101,1000}

1978/04/10 New 5P9693 Reusable Cable Tie For Storage Of Wires, Cables And Tubing{0630}

1978/04/10 New Piston Group With Better Service And Operation Characteristics Now Available{1214}

1978/04/03 A Gasket Group Is Available To Give Improved Sealing For The Oil Supply To The Rocker Arms On Early Engines{1101,1102,1221}

1978/04/03 Procedure For Alignment Of Transmission Mounting Parts On 1100 Series And 3208 Truck Engines With Allison MT640, MT650, And AT540 Series Transmissions{3000,1156,1157}

1978/03/27 Correct Adjustment Of The Governor Control Linkage In Truck Engines Is Necessary To Prevent Low Power{1265,1269}

1978/03/27 More Torque Now Used To Tighten The Retainer Nut For Turbocharger Compressor{1052,1053}

1978/04/24 Cylinder Block Has New Cover With An Oil Return Connection For Rockford Fan Drive{1201}

1978/04/24 Improved Water Separator Element And Retaining Clamp Stops Fuel Leakage{1250}

1978/04/24 New Oil Pressure Gauge Available For Marine Transmissions Used On D348, D349, D353, D379, D398, D399, 3406 And 3408 Marine Engines{7457,3300}

1978/05/01 5P8719 Hydraulic Hand Pump Decreases The Time Needed To Move Ram Pistons Under No Load{0621}

1978/05/01 New 5P8709 Piston Tool Group For The Alignment Of Piston Cooling Jets{0650}

1978/05/01 Correct Installation Of Lip-Type Seals In Hydraulic Oil Pumps{5055,5073}

1978/05/01 O-Ring Seals Of A Different Material Are Now Used On The Outside Diameter Of The Servo Cylinder In Governors{1264}

1978/05/01 External (Outside) Oil Lines Now Used Instead Of The Oil Passage In The Cylinder Block And Flywheel Housing{1307}

1978/05/01 Double-Walled Fuel Injection Lines Protect Unattended Industrial And Marine Engines{1252,0353}

1978/05/01 Improved Tube Assemblies For Engine Oil Lines{1307}

1978/05/01 New 5P7335 Rack Adjusting Tool Available{0654,1257,1264}

1978/05/01 Water Separator Added To Give Protection To The Sleeve Metering Fuel System{1250}