1992/08/31 Caterpillar

Connecting Rod Bearing Eliminates The Need For Mid-Life Connecting Rod Bearing Roll-In{1219,1202}

Usage:

3406 (90U),
3406B (6TB, 4FD, 1RK),
3408 (67U),
3408B (6NB, 9TD, 6RJ),
3412 (7DB, 9XF, 3NK, 38S) Industrial Engines;
3406 (91U),
3406B (4TB),
3408 (1LG, 8RG, 99U),
3412 (3JK, 60M) Marine Engines;
3406 (75Z),
3406B (2WB, 3SF, 4RG, 4JK),
3408 (2BG, 78Z) Generator Set Engines

Description of Change: A material change in the new connecting rod bearing provides improved fatigue resistance. This eliminates the need for a mid-life bearing roll-in.

Adaptable To: The new 9Y9497 Connecting Rod Bearing is a direct replacement for the former 1W7524 Connecting Rod Bearing. The former bearing is canceled. The new bearing is in effect as shown in the chart. The new bearing is adaptable to first production of all the above engines. Engines that are built, repaired, or overhauled with the new 9Y9497 Connecting Rod Bearings, DO NOT require a mid-life connecting rod bearing roll-in if the following conditions are NOT encountered:

* Extended operation at high load factors.

* Extended operation at high rpm (2100 rpm and above).

* Excessive lead or aluminum in oil samples.

* Reuse of Crankshaft with marginal profile or surface texture.

* Engine overheating.

* Oil dilution by fuel or coolant.

* Rapid cold engine starts.

* Dry starts after an engine has set for 30 or more days without prelubing.

* Extended oil drain intervals causing excessive lube oil sooting.

* Plugged oil filters.

* Incorrect oil viscosity (too light during hot weather, or too heavy during cold weather).

If these or similar conditions cause marginal lubrication to an engine, Caterpillar recommends the bearings be inspected and/or replaced.

Caterpillar Information System:

1992/08/31 Be Sure The Fuel Injection Pump Housing Is Compatible With 0R0715 And 0R2545 Remanufactured Short Blocks{1201,1253}

1992/08/31 New "3406B Engine Instructor Manual" Available{0374}

1992/08/31 New Deutsch HD-10® Electrical Connectors Used{1400}

1992/08/24 New Cylinder Head Group Provides Lower Valve Guide Temperatures {1100,1104,1112,1123}

1992/08/24 Reusability of Exhaust Valves in All Caterpillar Engines {1105}

1992/08/24 New Electronic Unit Injector (EUI) With New Style Solenoid Used; New Unit Injector Wiring Group Used {1290}

1992/08/24 Application Changes For Electronic Unit Injector (EUI) Part Numbers {1290}

1992/08/10 New Carrier Assembly Used In Governor And Fuel Pump Drive Groups {1288,1299}

1992/08/10 Proper Alternator Bench Testing {1405,1400}

1992/08/10 Taller Water Seals Used In Cylinder Head Groups {1115}

1992/07/27 Boxes/Cartons Containing Used Cores Should Be Immediately And Clearly Identified{0661}

1992/07/27 New Hardware Used In Water Lines Group{1380}

1992/08/31 Supplemental Coolant Additive Requirements{1352,1395,1063}

1992/09/07 Governor Specifications Are Available Through The Technical Information System{1264,0374}

1992/09/07 Major Engine Component Changes{1201,1202,1205,1218,1219,1230,1253,1288,1331}

1992/09/21 Replacement Mechanical Temperature And Pressure Gauges (Indicators) Retained By Push-On Metal Retainers{7450}

1992/09/21 New Plug And O-Ring Can Help Prevent Oil Leakage At The Flywheel Housing Gasket{1157,1307}

1992/09/21 New Fuel Injection Pump Groups Have Larger Diameter Camshaft Bores, New Lifter Assembly, And Shorter Plunger And Barrel Assembly{1251,1253,1281,1292}

1992/09/28 New Self Locking Bolt Used On Engine Side Covers {1201}

1992/09/28 Service Tools Available {0600,0700}

1992/09/28 New NEXG4516 Marine/Industrial Service Program Module(SPM) Available {1900,0782}

1992/10/05 Thicker Head Gaskets Available For Use With Resurfaced Cylinder Blocks{1124}

1992/10/05 New Cylinder Head Groups Provides Lower Valve Guide Temperatures{1100,1104,1112,1123}

1992/10/05 Product Support Literature{0374}