1978/04/17 Caterpillar

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

Usage:

D8K Tractors;
583K Pipelayers;
D342 and G342 Engines

Description of Change: An improved yoke for the valve lifter guides, hardened flat washers and increased torque on the bolts for the yokes are used on the above models. These changes keep the valve lifter guides tight and decrease possible damage to the guide bores in the cylinder block and other areas of the valve mechanism. Formerly, the pads on the yokes were sometimes out of parallel alignment with each other. This caused the bolts to loosen and as a result, the guides became loose.

Location of parts.

Adaptable As: Direct replacement on all the earlier models shown. The part number of the 2B7114 Yoke did not change. But when the improved yoke is installed, remove the six (6) 3H3451 Locks and install twelve (12) 5M2894 Washers. Then tighten the bolts for the 2B7114 Yokes to a torque of 32 ± 5 lb ft (43 ± 7 N·m).

MODIFICATION: The former 2B7114 Yokes can be machined and used again. Put the yoke on a flat surface. With three pads on that surface, the fourth pad must not be more than .006" (0.15 mm) off the surface. If it is, the four contact pads on the bottom surface of the yoke can be machined so the pads are in parallel alignment with each other.

Caterpillar Information System:

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}

1978/03/27 5P4149 Conversion Group To Become A Discontinued Item On October 1, 1978{0650,1254}

1978/03/27 How To Find Correct Oil Change Intervals For Truck Engines Operated In Short Distance Applications (Pick Up And Delivery Service){1318,7500,0374}

1978/03/27 9N3700 Or 9N3299 Nozzle Assemblies Must Be Used On 3208 Engines That Are Equipped With Exhaust Gas Recirculation (EGR){1254}

1978/03/27 Improved Thrust Washers Now Used With Planet Gears{3000,3072,3106,3110,3003,3001,3100,3116,3159,3176,3107,5150,5165}

1978/03/27 5P8675 Extension Handle Available For General Uses{0614}

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

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

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

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

1978/04/24 Oil Grooves And Harder Gears Are Now Used In The Oil Pumps On 6.25" Bore Vee Engines{1304}

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}