1977/10/17 Caterpillar


Improved Main, Thrust And Connecting Rod Bearings Have Aluminum Alloy With More Strength{1230}

Usage:


1100 and 3100 Series Engines and 3208 Engines In All Applications;
613, 613B Tractors;
225 Excavators

SUPPLEMENT: 12/05/77

SERVICE MAGAZINE, OCTOBER 17, 1977, PAGE 3. In the article "Improved Main, Thrust and Connecting Rod Bearings Have Aluminum Alloy With More Strength" a former part number shown in Chart 6 is wrong. Change 9N7949 to read 9L7949. Also in Chart 6, change the outside diameter for 7N7614 from standard to .010" (0.25 mm).

In Chart 7, change the outside diameter for 9N3057 from .020" (0.25 mm) to .010" (0.25 mm). Also change the inside diameter for 9N3065 from .050" (1.27 mm) to .020" (0.51 mm).

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

Description of Change: Different main, thrust and connecting rod bearings are now used in the above models. The aluminum alloy in the new bearings is of a higher strength for better resistance to erosion. Also, the bond (method of fasten) between the aluminum alloy and steel is stronger.

Adaptable As: The new bearings are a direct replacement for the former bearings as shown in the charts that follow:


NOTICE

In some applications, when the former crankshaft is to be used with the 9N1255 Cylinder Block Service Group, a front main bearing with an upper half that does not have a center groove can be needed. The locating tab on this bearing is also in the center. When the former crankshaft is to be used with a new 9N1255 Cylinder Block Service Group, always check the upper half of the front main bearing in the former cylinder block, or check the crankshaft to find out which type of No. 1 (front) main bearing is needed, before the crankshaft is installed. For crankshafts that have an oil supply passage from the No. 1 (front) main bearing journal to the No. 1 rod bearing, install the main bearing that has an upper half with a groove. For crankshafts that have an oil supply passage from the No. 2 main bearing journal to the No. 1 rod bearing, install the main bearing without a groove in the upper half.


GENERAL INSTALLATION: When a 9N2136, 9N2137 or 9N2138 Short Block Group, or a 9N1255 Cylinder Block Service Group is to be installed or is already installed, use the information that follows:

The 9N1255 Cylinder Block Service Group has a front main bearing with a groove in the upper half and a locating tab in the center of the bearing. This bearing is the replacement for the earlier bearing that had an offset tab and a groove in the upper half of the bearing. Use Special Instruction Form GMG02555-01 to correctly install any of these replacement cylinder block groups.

For late 3208 Engines which already have a cylinder block with a groove in the front main saddle and a front main bearing without a groove in the upper half of the bearing, use the information that follows:

If a 9N1255 Cylinder Block Service Group is to be installed, do not use the 9N3070 Bearing sent with the group. Instead, use a front main bearing that does not have a groove in the upper half of the bearing. Again, use Special Instruction Form GMG02555-01 for correct installation instructions.


Comparison of narrow and wide design bearings.

Caterpillar Information System:

1977/10/17 Preparation Of Truck Engines For Cold Weather Operation{1300,1000}
1977/10/17 Fabricated Extension Prevents Fuel "Splash" During Injection Valve Testing{0650,1254}
1977/10/10 If The Fuel Setting Dimension Is More Than 7.00 MM, Remove The End Play Of The Camshaft To Make The Fuel Setting{1257,1286}
1977/10/10 Improved Oversize And Undersize Connecting Rod And Main Bearings With Higher Strength Aluminum Alloy{1203,1219,1230}
1977/10/10 Use Only The Larger Size Inserts To Make A Repair To Cylinder Block Counterbores For Cylinder Liners{1201,1216,1217}
1977/10/10 Troubleshooting The Tachometer System Of The 4S6553 Engine Instrument Group{0651}
1977/10/10 New Front Housing Has Stronger Boss For Alternator{1151}
1977/10/10 Fuel Transfer Pump Shaft With Chromium Plate{1256}
1977/10/10 Be Sure To Drain Oil From The BrakeSaver At Every Lubricating Oil Change Period{1318,1155}
1977/10/03 Do Not Use Plastic Tubing With Brass Couplings As A Fuel Supply Line{1274}
1977/10/03 Washer Removed From Variable Timing Unit{1206,1272}
1977/10/03 Turbocharger Heat Shields Are Stronger{1073}
1977/10/17 Separate Parts Of Oil Pump Cover Now Available{1304,1314}
1977/10/17 Vent Tube Added To Jacket Water Aftercooler{1063}
1977/10/24 Assembly Procedure For The 5P4721 Tube (Part Of The 5P4149 Conversion Group And 5P4150 Nozzle Testing Group){0650}
1977/10/24 Adjust Shop Tire Pressures For Operation In Cold Temperatures{4203,4204}
1977/10/24 New Piston Group Has Improved Iron Band In The Piston Body{1214}
1977/10/24 Replacement Bearings Have Aluminum Alloy With More Strength{1203,1213,1230}
1977/10/31 New Hydraulic Flow Meter Has Many Improvements To Make It Easier, Faster And Safer To Use Than The Former Flow Meter{0651,5050}
1977/10/31 New Governor Spring Changes Speed Regulation{1264,1286}
1977/10/31 With New 5P7448 Adapter, Earlier Fuel Injection Valves And Nozzles Can Be Tested And Adjusted On The 5P4150 Nozzle Testing Group{0651,1254}
1977/10/31 Some Wobble Is Acceptable In Rubber Vibration Dampers For Crankshafts{1205}
1977/11/07 Crankshaft Support Groups Are Available To Measure Bent Crankshafts{0653,1202}
1977/11/07 Improved Crankshaft Main Bearings And Connecting Rod Bearings With Higher Strength Aluminum Alloy{1203,1219,1230}
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.