Inspection and Reconditioning Procedures of Main Bearing Bores in Cylinder Blocks {1201, 1202, 1224, 1224} Caterpillar

Caterpillar Products

All Cat Engines

Introduction

© 2019 Caterpillar® All Rights Reserved. This guideline is for the use of Cat dealers only. Unauthorized use of this document or the proprietary processes therein without permission may be violation of intellectual property law.

Information contained in this document is considered Caterpillar: Confidential Yellow.

This Reuse and Salvage Guideline contains the necessary information to allow a dealer to establish a parts reusability program. Reuse and salvage information enables Caterpillar dealers and customers to benefit from cost reductions. Every effort has been made to provide the most current information that is known to Caterpillar. Continuing improvement and advancement of product design might have caused changes to your product which are not included in this publication. This Reuse and Salvage Guideline must be used with the latest technical information that is available from Caterpillar.

For technical questions when using this document, work with your Dealer Technical Communicator (TC).

To report suspected errors, inaccuracies, or suggestions regarding the document, submit a form for feedback in the Service Information System (SIS Web) interface.

Canceled Part Numbers and Replaced Part Numbers

This document may not include canceled part numbers and replaced part numbers. Use NPR on SIS for information about canceled part numbers and replaced part numbers. NPR will provide the current part numbers for replaced parts.

Important Safety Information

Illustration 1	g02139237

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools to perform these functions properly. Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. If a tool, a procedure, a work method, or operating technique that is not recommended by Caterpillar is used, ensure that it is safe for you and for other people to use. Ensure that the product will not be damaged or the product will not be made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.

Show/hide table

Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information.

Safety precautions and warnings are provided in this manual and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons.

The hazards are identified by the safety alert symbol which is followed by a signal word such as danger, warning, or caution. The "WARNING" safety alert symbol is shown below.

Illustration 2	g00008666

This safety alert symbol means:

Pay attention!

Become alert!

Your safety is involved.

The message that appears under the safety alert symbol explains the hazard.

Operations that may cause product damage are identified by "NOTICE" labels on the product and in this publication.

Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The safety information in this document and the safety information on the machine are not all inclusive. Determine that the tools, procedures, work methods, and operating techniques are safe. Determine that the operation, lubrication, maintenance, and repair procedures will not damage the machine. Also, you must determine that the operation, lubrication, maintenance, and repair procedures will not make the machine unsafe.

The information, the specifications, and the illustrations that exist in this guideline are based on information which was available at the time of publication. The specifications, torques, pressures, measurements, adjustments, illustrations, and other items can change at any time. These changes can affect the service that is given to the product. Obtain the complete, most current information before you start any job. Caterpillar dealers can supply the most current information.

Summary

This guideline provides the inspection procedure and the reconditioning procedure for main bearing bores. This guideline applies to cylinder blocks for all engines regardless of bore size. Cylinder blocks that meet the requirement in this guideline and in the applicable guidelines for specifications can be expected to give normal performance in the same application until the next engine overhaul.

Service Letters and Technical Information Bulletins

References

Tooling and Equipment

Replacement Parts

Consult the applicable Parts Identification manual for your engine.

Show/hide table

When replacement parts are required for this product Caterpillar recommends using Caterpillar replacement parts or parts with equivalent specifications including, but not limited to, physical dimensions, type, strength and material. Failure to heed this warning can lead to premature failures, product damage, personal injury or death.

Measurement Requirements

Inspection

Inspection of Bearings

Illustration 3	g06305181
Uneven wear pattern on main bearings

Illustration 4	g01449229
Uneven wear pattern on main bearings

Illustration 5	g01450593
Uneven wear pattern on main bearings

Illustration 6	g01450640
Uneven wear pattern on main bearings

1. Inspect main bearings and thrust bearings for wear patterns. Look for side loading, uneven wear patterns, damage, and fretting.

Refer to Reuse and Salvage Guideline, SEBF8064, "Reuse and Salvage for Connecting Rods" for pictures and information about the wear of bearings.

Inspection of the Crankshaft

Illustration 7	g06305185
Crankshaft on vee blocks with dial indicator

1. Inspect the crankshaft journals for wear and damage.

2. Inspect the oil holes for debris.

3. Inspect the fillets for pitting and scalloped edges.

4. Inspect the crankshaft for any damage to the counterweights.

Refer to Reuse and Salvage Guideline, SEBF8042, "Reuse and Salvage for Crankshafts" for more information regarding inspection of crankshafts.

Inspection of Main Bearing Caps

Show/hide table

Illustration 8	g01436433
(1) Fretting

Show/hide table

Illustration 9	g01441317
Physical damage to the saddle of the main bearing cap

1. Main bearing caps should be visually inspected for any obvious damage.
   Show/hide table

   Illustration 10	g01986344
   Inspection of flatness on main bearing cap

2. After the visual inspection, the caps should be measured for flatness. Place the caps on a precise flat surface. If a 0.038 mm (0.0015 in) feeler gauge can fit under the flat surfaces of the cap, then the cap must be machined. Refer to "Procedure to Machine Main Bearing Caps" for the machining procedure.

   Note: The flatness of the precise flat surface should only vary 0.005 mm (0.0002 inch).

3. Inspect the main bores for damage. Feel for galling or high spots on the bores.
   Show/hide table

   Illustration 11	g06305193
   (2) Gap between the cap and block

4. Install the main bearing caps on the cylinder block.

   Note: The location and orientation of the caps is critical.

5. Inspect the width of the cap in relation to the width of the space in the cylinder block. Force the cap to one side.

6. Insert a feeler gauge between the cap and the block. If a 0.040 mm (0.0016 inch) feeler gauge will fit, then the cap must be replaced or salvaged.

Inspection of Out of Round and Taper

Show/hide table

Illustration 12	g01436907
Positions to measure out of roundness

1. Torque the caps to full torque. Refer to the appropriate specifications manual for the torque procedure and the tightening sequence.
   Show/hide table

   Illustration 13	g01986348
   Measurement for out of round with a dial bore gauge

2. Measure the main bores for the crankshaft with a dial bore gauge. Take measurements in the vertical position, the horizontal position, and 45° positions. These measurements will be used to determine if the bore is out of round. Refer to Illustration 12 for the out of round measurement.

3. Take a vertical measurement in the front and rear of each bore. The difference between these two measurements is the taper of the bore.

Refer to the appropriate specifications manual for the specific information about both of these measurements. If the bores exceed specifications, then the bores must be machined. Refer to "Procedure to Line Bore Using the 1P-4000 Line Boring Tool Group" for the machining procedure.

Inspection of Alignment of Main Bores

Show/hide table

Illustration 14	g01986359
Boring bar in main bores

1. Use the boring bar from 1P-4000 Line Boring Tool Group to check the main bores for alignment. Place the boring bar in the main bores.

2. Roll the boring bar slightly in one direction. Place a 0.025 mm (0.0010 inch) feeler gauge onto the main bore.

3. Allow the boring bar to roll over the feeler gauge. Pull on the feeler gauge. If there is resistance, then the bore is in alignment. If the feeler gauge is easily removed, then the bore is out of alignment. If the bore is out of alignment, line bore the block.

4. Use this process in the same eight locations as the out of round measurement. Refer to Illustration 12 for the out of round measurement.

Refer to "Procedure to Line Bore Using the 1P-4000 Line Boring Tool Group" for information about the line boring process.

Repair Process

Note: This repair process is for components that do not pass the inspection.

Crankshaft

Refer to Reuse and Salvage Guideline, SEBF8042, "Reuse and Salvage for Crankshafts" for information about machining crankshafts.

Procedure to Machine Main Bearing Caps

Note: The flats of the main bearing caps should not be machined until Step 2 in "Procedure to Line Bore Using the 1P-4000 Line Boring Tool Group".

Illustration 15	g01986475
An example of a boring machine setup.

1. Position the vise on the boring machine. Use a dial indicator to indicate the vise to the spindle. Clamp the vise to the table.
   Show/hide table

   Illustration 16	g01986499
   Remove burrs.

2. Use a stone to remove any burrs from the opposite side.

3. Place the cap into the vise. Clamp the vise. Tap on the cap with a soft hammer. This will locate the cap in the bottom of the vise.
   Show/hide table

   Illustration 17	g01986504

4. Use a 0.025 mm (0.0010 inch) feeler gauge to verify the location of the cap in the vise.

   Note: Make this verification on both sides of the cap.

   Show/hide table

   Illustration 18	g01986533

5. Remove 0.08 mm (0.003 inch) to 0.13 mm (0.005 inch) from both faces. Allow the cutter to move across both faces. It is not necessary for all caps to be the same height.

6. Remove burrs.

Repeat step 1 through step 6 for the remaining caps.

Note: New replacement caps are available if machining the main caps is not the preferred method. If the caps are replaced, it is necessary to line bore the block.

Procedure to Line Bore Using the 1P-4000 Line Boring Tool Group

Show/hide table

Illustration 19	g01986634
(3) Boring Bar (4) Centering Ring

1. Place centering rings in the first main bearing bore, the third main bearing bore, the fifth main bearing bore, and the seventh main bearing bore.

2. Remove 0.08 mm (0.003 inch) to 0.13 mm (0.005 inch) from both faces of the second main bearing cap, the fourth main bearing cap, and the sixth main bearing cap. Refer to "Procedure to Machine Main Bearing Caps" for the machining procedure.

3. Install the second main bearing cap, the fourth main bearing cap, and the sixth main bearing cap.

4. Torque all the main bearing caps to full torque. Refer to the appropriate specifications manual for the torque procedure and the tightening sequence.
   Show/hide table

   Illustration 20	g01986654
   The dial indicator is being used to set the size of the cutting tool.

   Show/hide table

   Illustration 21	g01986656
   Boring bar with cutting tool

5. Set the cutting tool to the appropriate size. Use the information from "Inspection" to determine the appropriate size. Refer to the corresponding specifications manual.

6. Apply oil to the centering rings and the boring bar. Place boring bar in centering rings. Install the cutting tool onto the boring bar.
   Show/hide table

   Illustration 22	g01986673
   Hydraulic Drive

7. Verify that the hydraulic drive is moving in the correct direction.
   Show/hide table

   Illustration 23	g01986337

8. Use a drill to turn the boring bar. Use a swivel joint from the 1P-4000 Line Boring Tool Group with the drill. This will help avoid mistakes.

9. Machine the second main bearing bore, the fourth main bearing bore, and the sixth main bearing bore. Do not move the centering rings until these bores have been completed.
   Show/hide table

   Illustration 24	g06305252
   The clamp (5) is holding the centering ring (4) in place.

10. Move the centering rings to the second main bearing bore, the fourth main bearing bore, and the sixth main bearing bore.

11. Remove 0.08 mm (0.003 inch) to 0.13 mm (0.005 inch) from both faces of the third main bearing cap and the fifth main bearing cap. Refer to "Procedure to Machine Main Bearing Caps" for the machining procedure.

12. Install the third main bearing cap and fifth main bearing cap. Torque the third main bearing cap and fifth main bearing cap to full torque. Refer to the appropriate specifications manual for the torque procedure and the tightening sequence.

13. Machine the third main bearing bore and the fifth main bearing bore.

    Note: Clamps may be necessary to keep centering rings in place.

    Show/hide table

    Illustration 25	g01986748
    (6) Upright Bearing Assembly (7) Bridge Assembly

14. Place the bridge assembly on the block. The bridge assembly must be in front of the seventh main bearing bore.

15. Bolt the bridge assembly to the block. Do not tighten the bolts at this time. Refer to Illustration 25.

16. Install the upright bearing assembly into the bridge assembly. Tighten the bolts by hand.

17. Install the boring bar through the centering rings and bearing assembly.

    1. Slide the boring bar back and forth while the bolts are being tightened. This will allow the upright bearing assembly to be aligned with the other bores.

    2. Move the boring bar out of the upright bearing assembly. Slowly move the boring bar in the upright bearing assembly. Listen and feel for any contact. If any contact is detected, the upright bearing assembly is not aligned with the other bores. Repeat this process until no contact occurs.

18. Remove 0.08 mm (0.003 inch) to 0.13 mm (0.005 inch) from both faces of the seventh main bearing cap. Refer to "Procedure to Machine Main Bearing Caps" for the machining procedure.

19. Install the seventh main bearing cap. Torque the seventh main bearing cap to full torque. Refer to the appropriate specifications manual for the torque procedure and the tightening sequence.

20. Install the cutting tool on the boring bar outside one of the outer bores.

21. Install the hydraulic drive and switch directions.

22. Machine the seventh bore.

23. Repeat steps 14 through 22 for the first main bearing bore.

24. Verify the machining procedure. Place centering rings in the outer bores. Move the boring bar in and out of the centering rings. Listen and feel for any contact between the boring bar and the centering rings. If any contact is detected, the bores are not in alignment.