2001/07/23 Caterpillar

Track-Type Tractor:

D6D (S/N: 7XF; 75W; 05X; 01Y)

D6E (S/N: 8FJ)

D6G (S/N: 2MJ; 3SR)

D6H (S/N: 8KB; 3ED; 2DK; 1FJ)

D6R (S/N: 2HM; 4FM; 4MN; 8TM; 9BM; 2YN; 3ZN; 4HN; 5LN; 6JN; 7KN; 8LN; 8XN; 9MN; 9PN; 4JR; 4TR; 4WR; 5PR; 5RR; 6FR; 6GR; 6HR; 6MR; 7AR; 7DR; 7GR; 9ZS; 1RW)

Motor Grader:

12H (S/N: 4XM; 8MN; 2WR; 4ER)

14H (S/N: 7WJ)

140H (S/N: 2ZK; 5HM; 8JM; 8KM; 9TN; 9ZN; 3HR; 3AS)

143H (S/N: 1AL)

160H (S/N: 9EJ; 2FM; 3GM; 6WM; 9JM; 3HR; 2HS)

163H (S/N: 5AK)

Wheel Skidder:

528 (S/N: 96C; 97C; 51S; 78W)

528B (S/N: 8SJ)

530B (S/N: 5BK)

If the forward exhaust stud fails on the 3306 engine, additional service life may be obtained from the replacement studs by a simple machining operation to the exhaust manifold. The flats for the retaining washers on the exhaust manifold are not spot faced. The two flats at the ends have a draft angle, which causes the stud to bend as the nut is tightened. This bending increases the forces on the stud during the heating and cooling cycle of the exhaust manifold.

The repair procedure machines the surface of the flat parallel to the gasket surface of the manifold. Replacement studs which have a longer service life are available. New spacers are available to center the manifold on the studs during the installation.

Repair Procedure

Reference: Disassembly and Assembly, SENR5598, "Exhaust Manifold - Remove and Install"

1. Follow the procedure in the Disassembly and Assembly for the removal of the manifold. Check the exhaust manifold for cracks. Check the exhaust manifold for warping. Replace the manifold with a three-piece manifold if the manifold is not reusable.

2. Use a drill and an extractor to remove the broken stud. Remove the end studs and any other studs that you are replacing. Clean the gasket surfaces.

Note: Apply 5P-3931 Anti-Seize Compound to the threads of the studs before installation.

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Illustration 1	g00787435

3. In front position (1), replace the 106-1793 Taperlock Stud with a 205-3202 Taperlock Stud. In rear position (3), replace the 6V-1426 Taperlock Stud with a 205-3203 Taperlock Stud. Replace the remaining 6V-1426 Taperlock Studs with 205-3203 Taperlock Studs, if desired. Tighten the studs to 27 ± 4 N·m (20 ± 3 lb ft).

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Illustration 2	g00787433

4. If you reuse the one piece exhaust manifold, grind surface (B) of the flat in the forward position parallel with gasket surface (A) of the manifold. Grind gasket surface (A) of the manifold flat, if necessary.

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Illustration 3	g00787465

5. Install three new 9Y-1979 Manifold Gaskets (4). Take care to orient the gaskets according to the directions on the tab.

6. Install the two 203-4184 Spacers on the second stud (2) from each end. Install the one piece manifold over the spacers.

Note: Apply 5P-3931 Anti-Seize Compound to the threads of the studs before installation.

7. Install washers and nuts on the studs at each end of the manifold. Hand tighten the nuts in order to hold the manifold in position.

8. Remove the spacers. Install the remaining washers and nuts, except for the two studs that hold the heat shield.

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Illustration 4	g00787466

9. On the last two studs install these components: the two large washers, the spacers, heat shield (5), the remaining two hard washers and the nuts.

10. Tighten the nuts to a torque of 47 ± 4 N·m (35 ± 3 lb ft).

11. Follow the procedure in the Disassembly and Assembly in order to complete the repair.