C18 Marine Engines Caterpillar

Removal Procedure

Start By:

1. Remove the front housing.

2. Remove the flywheel housing.

3. Remove the piston cooling jets.

1. Check the main bearing caps for identification for the location and the direction in the cylinder block. The identification marks on the main bearing caps must be installed in the same direction prior to removal.

2. Check the connecting rod and the connecting rod bearing caps for identification and the location in the cylinder block.
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   Illustration 1	g01017945

3. Remove bolts (1) for connecting rod bearing cap (2). Remove the connecting rod bearing caps.
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   Illustration 2	g01020310

4. Remove bolts (3) for main bearing cap (4). Remove the main bearing caps.
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   Illustration 3	g00996555

5. Install Tooling (A) and a suitable lifting device on each end of crankshaft (5). The weight of crankshaft (5) is approximately 177 kg (390 lb).

6. Remove the crankshaft from the cylinder block.

7. Remove the thrust plates from each side of the No. 4 main bearing.

8. Remove the lower main bearings from the main bearing caps. Remove the upper main bearings from the cylinder block.

   Note: Mark the used main bearings or identify the used main bearings for installation if the main bearings will be used again.

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   Illustration 4	g00996556

9. Use Tooling (B) to remove crankshaft gear (6) from crankshaft (5).
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   Illustration 5	g01056151

10. If necessary, use Tooling (C) to remove dowel (7) and dowel (8) from crankshaft (5).

Installation Procedure

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Illustration 6	g01018035

1. Install dowel (7) in the crankshaft.

   Protrusion of dowel (7) from the crankshaft face ... 6.4 mm (0.25 inch)

2. Install dowel (8) in the crankshaft.

   Protrusion of dowel (8) from the crankshaft ... 4.1 ± 0.5 mm (0.16 ± 0.02 inch)

   Note: Do not use a torch to heat the crankshaft gear. Overheating of the crankshaft gear will cause premature failure.

3. Raise the temperature of crankshaft gear (6) to a maximum temperature of 233° C (451° F). Install crankshaft gear (6) on the crankshaft with the keyway in alignment with dowel (8). The Timing Mark "V" of the gear should face away from crankshaft (5). If necessary, use a suitable brass drift and a suitable hammer to seat the crankshaft gear against the shoulder of the crankshaft.

4. Clean the cylinder block and the main bearing caps thoroughly.
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   Illustration 7	g01048335

   Note: Install the main bearings dry when clearance checks are performed. Refer to Disassembly and Assembly, "Bearing Clearance - Check". Apply clean engine oil on the face of the main bearings for final assembly.

5. Install the upper halves of main bearings (9) in the cylinder block.

   Note: Ensure that the main bearings are installed so that the bearing tabs fit into the notch in the cylinder block. The upper halves of the main bearings have the oil groove and the oil hole.

6. Install Tooling (A) and a suitable lifting device on crankshaft (5). The weight of crankshaft (5) is approximately 177 kg (390 lb).

7. Install crankshaft (5) with the Timing Mark "V" on the crankshaft gear in alignment with the Timing Mark "V" on the cluster gear.
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   Illustration 8	g01048338

8. Install thrust plates (10) on each side of the No. 4 main bearing.

   Note: Install the thrust plates with the words "Block Side" toward the cylinder block.

9. Install the lower halves of the crankshaft main bearings in the main bearing caps.

   Note: Ensure that the main bearings are installed so that the bearing tabs fit into the notch in the main bearing cap.

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   Illustration 9	g01020434

10. Position main bearing caps (4) on the crankshaft.

    Note: Ensure that the numbers on the main bearing caps match the numbers on the cylinder block. Also ensure that the "FRONT" on the main bearing cap is installed toward the front of the cylinder block.

11. Lubricate the threads of bolts (3) with clean engine oil. Install the bolts.

12. Tighten bolts (3) for the main bearing caps, as follows:

    1. Tighten Bolt (A) to a torque of 258 ± 14 N·m (190 ± 10 lb ft).

       Note: Bolt (A) is on the bearing tab side of the main bearing cap.

    2. Tighten Bolt (B) opposite the bearing tab side to a torque of 258 ± 14 N·m (190 ± 10 lb ft).

       Note: Bolt (B) is on the opposite side of the bearing tab of the main bearing cap.

    3. Tighten Bolt (B) for an additional 120 ± 5 degrees (2 flats).

       Note: If Tooling (E) is not used, place an index mark on the bolt and the main bearing cap.

    4. Tighten Bolt (A) for an additional 120 ± 5 degrees (2 flats).

       Note: If Tooling (E) is not used, place an index mark on the bolt and the main bearing cap.

    5. Rotate the crankshaft in order to ensure that the crankshaft turns freely.
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    Illustration 10	g01103661

13. Use Tooling (D) to check the crankshaft end play. Ensure that Tooling (D) is against a machined surface. The end play is controlled by the thrust plates of No. 4 main bearing (center). Refer to Specifications, "Crankshaft" for the crankshaft end play.

    Note: Install the connecting rod bearings dry when clearance checks are performed. Refer to Disassembly and Assembly, "Bearing Clearance - Check". Apply clean engine oil on the face of the connecting rod bearings for final assembly.

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    Illustration 11	g01020428

14. Position the connecting rod against the crankshaft. Install connecting rod bearing cap (2) on the connecting rod.

    Note: Ensure that the number on the side of the connecting rod bearing cap is on the same side as the number on the connecting rod. The bearing tabs of the connecting rod bearing cap and the connecting rod are located on the side of the piston cooling jet.

15. Lubricate the threads of bolts (1) with clean engine oil. Install the bolts.

16. Tighten bolts (1), as follows:

    1. Tighten Bolt (A) and Bolt (C) to a torque of 70 ± 4 N·m (52 ± 3 lb ft).

    2. Tighten Bolt (B) and Bolt (D) to a torque of 70 ± 4 N·m (52 ± 3 lb ft).

    3. Turn Bolt (B) and Bolt (D) for an additional 60 ± 5 degrees (1/6 turn).

       Note: If Tooling (E) is not used, place an index mark on each bolt and connecting rod cap.

    4. Tighten Bolt (A) and Bolt (C) to a torque of 70 ± 4 N·m (52 ± 3 lb ft).

    5. Turn Bolt (A) and Bolt (C) for an additional 60 ± 5 degrees (1/6 turn).

       Note: If Tooling (E) is not used, place an index mark on each bolt and connecting rod cap.

    6. Rotate the crankshaft in order to ensure that the crankshaft turns freely.

End By:

1. Install the piston cooling jets.

2. Install the flywheel housing.

3. Install the front housing.