Removal Procedure
| Required Tools | |||
| Tool | Part Number | Part Description | Qty |
| A | 6V-6080 | Torque Multiplier | 1 |
| B | 156-7168 | Main Bearing Tool Group | 1 |
| C | 153-8488 | Stud Tensioner Tool Gp (Crankshaft Main Bearing) | 2 |
| D | 156-7166 | Electric Hydraulic Pump Gp (1) | 1 |
| 156-7167 | Manual Hydraulic Pump (1) | 1 | |
| 178-9312 | Hose As | 2 | |
| 178-9313 | Coupler Block Gp | 1 | |
| E | 160-4901 | Tray Support | 2 |
| F | 160-0475 | Tray | 1 |
| G | 8T-2681 | Main Bearing Driver | 1 |
| H | 185-0683 | Pressure Gauge As (Comparison) | 1 |
| ( 1 ) | Either pump may be used for this procedure. |
| NOTICE |
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Keep all parts clean from contaminants. Contaminants may cause rapid wear and shortened component life. |
| NOTICE |
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Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Caterpillar Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Caterpillar products. Dispose of all fluids according to local regulations and mandates. |
Note: With this procedure, the main bearing caps can be lowered approximately 230 mm (9.0 inch). If the main bearing caps must be lowered further, additional equipment for jacking up of the main bearing cap will be required. For more information on the use of the Tooling, see Tool Operating Manual, NEHS0762.
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| Illustration 1 | g01214891 |
Tooling (B) (1) Lifting bracket (2) Lift assembly (3) Air cylinder (4) Base (5) Air control | |
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| Illustration 2 | g01214894 |
Tooling (C) (6) Stud tensioner support (7) Stud tensioner | |
- Drain the engine oil from the engine oil pan into a suitable container for storage or for disposal. Refer to Operation and Maintenance Manual, "Engine Oil and Filter - Change".
- Remove side covers (8) from both sides of the crankshaft main bearing that will be serviced. Remove side covers (8) from both sides of the engine. A total of four side covers must be removed for each crankshaft main bearing.
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| Illustration 3 | g01214902 |
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| Illustration 4 | g01214970 |
Typical example | |
- Use Tooling (A) to loosen bolts (9) that support the main bearing cap. Loosen bolts (9) on both sides of the engine. DO NOT remove bolts (9) at this time.
| NOTICE |
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Removal of the bolts that support the main bearing cap will allow the main bearing cap to fall when the nuts that support the main bearing cap are removed from the studs. This will cause damage to the engine. DO NOT remove the bolts that support the main bearing cap until the main bearing cap is supported by other means. |
- Remove thermocouple (10) from the main bearing cap that will be serviced. If necessary, remove the adjacent thermocouples in order to avoid damage to the harness assemblies.
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| Illustration 5 | g01214906 |
- Install lifting bracket (1) onto the main bearing cap. In order to secure the bracket to the main bearing cap, insert pins (11) through the holes in the bracket and through the main bearing cap. Make sure that the pins are fully inserted through both sides of the bracket.
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| Illustration 6 | g01214923 |
Rear view of the lifting bracket (typical example) | |
- Attach lift assembly (2) to the lifting bracket with pins (12). Make sure that the pins are properly installed.
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| Illustration 7 | g01214931 |
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Because of high pressure, a tight bending radius or a kink in a hose could cause the hose to break and result in personal injury. Do not allow the hoses to bend in a radius that is less than 250 mm (10 inch). Before you use a hose, always inspect the hose. Never use a hose that is damaged, defective, or kinked. |
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- Place the base with air cylinder (3) into the engine oil pan. Align the air cylinder under the center of lift assembly (2) .
- Make sure that the hoses for the pressurized air supply to the air cylinder are properly attached. Place the air control at an accessible location that is outside of the engine.
- Install stud tensioner supports (6) onto the studs for the main bearing cap. Rotate each stud tensioner support in order to engage the drive ring of the stud tensioner support with the flats of the nut. When the stud tensioner support is properly installed, the stud tensioner support will rest against the washer. Secure each stud tensioner support with pins (13) .
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| Illustration 8 | g01214978 |
Rear view of the lifting bracket (typical example) | |
- Place Tooling (E) onto the baffles that are inside of the engine oil pan. Make sure that the notches in Tooling (E) fit into the baffles. Place Tooling (F) onto Tooling (E). Make sure that the raised end of Tooling (F) is away from the main bearing cap. Place the stud tensioners onto Tooling (F). Move Tooling (F) toward the main bearing cap.
Note: It is not necessary to perform Step 10 in order to complete the procedure. However, Tooling (E) and Tooling (F) will aid in the handling of the stud tensioners.
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| Illustration 9 | g00640464 |
- Carefully lift stud tensioners (7) onto the lift assemblies. Be careful not to damage the threads of the studs. Make sure that the hydraulic fittings of both stud tensioners (7) are oriented in the same direction.
The lift assembly may seem unstable when the stud tensioners are placed onto the lift assembly. This is normal. The lift assembly is spring loaded in order to allow the threads of the tensioners to be aligned with the threads of the studs.
If Tooling (F) was used for the handling of the stud tensioners, move Tooling (F) away from the main bearing cap.
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| Illustration 10 | g01214988 |
- Turn OFF the air supply valve and the exhaust valve of air control (5). Then open both valves for approximately 1/4 turn (90 degrees). This will help to prevent the lifting bracket from operating at a speed that is too fast.
The valves of the air control can be adjusted for optimum operation.
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| Illustration 11 | g01214996 |
Air control (5) (W) Cylinder "UP" (X) Cylinder "DOWN" (Y) Air supply valve (Z) Air exhaust valve | |
- Operate the air control with a pulsing motion. Press the "UP" button and release the button on the air control in order to slowly extend the piston of the air cylinder. Raise the piston into the countersunk ring of the lift assembly. If necessary, realign the base in order to center the piston. Extend the piston until the piston fully contacts the lift assembly.
- Use enough air pressure for the piston to support the lift assembly. Then remove pins (12) that attach the lift assembly to the bracket.
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| Illustration 12 | g01215015 |
- Position stud tensioners (7) in order to align the threads of the Tooling with the studs. Use the air control to slowly lift the stud tensioners onto the bottoms of the studs. Start screwing one of the stud tensioners onto the stud and then start screwing the other stud tensioner. This will help to prevent the lift assembly from tilting.
Use the 1/2 inch square drive that is on the bottom of the stud tensioners in order to fully thread the stud tensioner onto the studs. After the stud tensioners have been fully tightened, reverse the threads for one and one-half turns (540 degrees).
Do not reverse the threads excessively. The hydraulic cylinders will not operate properly if the distance is more than the maximum stroke.
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| Illustration 13 | g01215017 |
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Because of high pressure, a tight bending radius or a kink in a hose could cause the hose to break and result in personal injury. Do not allow the hoses to bend in a radius that is less than 250 mm (10 inch). Before you use a hose, always inspect the hose. Never use a hose that is damaged, defective, or kinked. |
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Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak. |
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A hydraulic cylinder and/or a hose that is not secure can be released when hydraulic pressure is applied. This can cause severe personal injury. When you are applying hydraulic pressure, always stay a distance of 3 to 5 m (10 to 16 ft) away from the cylinders and the hoses. When pressure is applied to the cylinders, always keep body parts away from the direction of the force. Always wear safety glasses when you work with hydraulic equipment. Use the minimum amount of pressure that is necessary. Always release the pressure when the equipment is not supervised. Never modify the equipment without written permission from the manufacturer. |
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- Use Tooling (H) to verify the gauge on the hydraulic pump in Tooling (D). If the readings of the two gauges vary by more than one percent of the maximum gauge pressure, do not use the hydraulic pump.
For example, two gauges have a maximum pressure of 160 MPa (23,206 psi). The test pressure of the gauges must be within 1.6 MPa (232 psi).
Make sure that the gauge on the hydraulic pump is correct. Position the hydraulic pump so that the pressure gauge and the hydraulic cylinders can be observed.
- Connect the hydraulic lines of Tooling (D) to the stud tensioners and to the hydraulic pump.
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| Illustration 14 | g00640830 |
- Operate the pump to a pressure of 125 ± 2.5 MPa (18,130 ± 365 psi). Make sure that the pressure is maintained. This will stretch the stud in order to move the nut away from the crankshaft main bearing.
- Use the square drive on stud tensioner support (6) to loosen the nuts until the nuts contact the stud tensioners. Do not apply more than 100 N·m (75 lb ft) of torque.
If the nuts will not loosen, Repeat Step 18 and apply an additional 5 MPa (725 psi) of hydraulic pressure.
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| Illustration 15 | g01215021 |
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Personal injury can result from removing hoses and/or disconnecting couplings in a pressurized system. Failure to relieve the pressure can cause personal injury. Do not remove the hoses or disconnect the couplings until the pressure has been relieved. |
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- Slowly release the hydraulic pressure. After the hydraulic pressure has been released, disconnect the hoses from the stud tensioners.
- Unscrew stud tensioners (7) from the studs. Carefully place the stud tensioners onto the lift assembly. Raise the lift assembly, if necessary.
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| Illustration 16 | g01214988 |
- Use the air control to slightly lower the lift assembly. Attach the lift assembly to the bracket with pins (12) .
If Tooling (F) is used, move Tooling (F) close to the main bearing cap. Place stud tensioners (7) onto Tooling (F). Move Tooling (F) away from the main bearing cap.
If Tooling (F) is not used, remove the stud tensioners from the engine oil pan.
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| Illustration 17 | g01215027 |
- Remove pins (13) and remove stud tensioner supports (6) .
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| Illustration 18 | g01214978 |
- Remove pins (12) from the bracket. Use the air control to fully extend the lift assembly. Unscrew nut (14) from the stud.
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| Illustration 19 | g01215029 |
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Severe personal injury can result if the bearing cap falls on a body part or pinches a body part. During removal and installation of the bearing cap, stay away from the bearing cap until the bearing cap is secured. |
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- Make sure that pressurized air is supplied to the air cylinder. The lift assembly will be supporting the main bearing cap. The weight of the main bearing cap is approximately 81 kg (180 lb). Use Tooling (A) to remove bolts (9) that support the main bearing cap.
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| Illustration 20 | g01214970 |
- Use a pulsing motion to operate the air control. Press the "DOWN" button and release the button on the air control in order to slowly lower the main bearing cap.
- Note the location of the tab on the end of crankshaft main bearing (15). A corresponding tab is on the upper half of the crankshaft main bearing. Remove the lower half of crankshaft main bearing (15) from the main bearing cap. Mark the lower half of the crankshaft main bearing for identification.
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| Illustration 21 | g01215033 |
- Install Tooling (G) into the oil hole of the main bearing journal. Make sure that the short end of the blade will press against the crankshaft main bearing when the crankshaft is rotated. Rotate the crankshaft in the direction that will first remove the end of the crankshaft main bearing that has a tab.
As the crankshaft is rotated, Tooling (G) will push the upper half of the crankshaft main bearing out of the main bearing journal. Remove the upper half of the crankshaft main bearing from the engine.
| NOTICE |
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The upper half of the main bearing has a tab. If the tab is pushed against the crankshaft, the cylinder block, the bearing, and the crankshaft can be damaged. When you remove the upper half of the bearing, always rotate the crankshaft so that the tab is the first part of the bearing to be removed. When you install the upper half of the bearing, always rotate the crankshaft so that the tab is the last part of the bearing to be installed. |
| NOTICE |
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The main bearing driver can be broken if the long end of the blade is used to install the bearing. Always use the short end of the blade to install the bearing. |
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| Illustration 22 | g01215827 |
Short end of the blade | |
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| Illustration 23 | g00649327 |
- Unless Tooling (G) will be used next in the same main bearing journal, continue to rotate the crankshaft in order to remove Tooling (G) from the main bearing journal.