Series 55 – Section 7.2 Exhaust Manifold

Section 7.2
Exhaust Manifold

The exhaust is a single piece manifold. The outlet flange is centrally located and connects directly to the turbocharger turbine housing. The exhaust manifold is attached to the cylinder heads with twelve special alloy hardened bolts. Six identical exhaust manifold gaskets are used between the exhaust manifold and the cylinder heads. See Figure "Exhaust Manifold" .‪

1.Exhaust Manifold‪

2.Turbocharger Outlet Flange‪

Figure 1. Exhaust Manifold

Section 7.2.1
Repair or Replacement of Exhaust Manifold

To determine if repair or replacement of the exhaust manifold is necessary, perform the following procedure. See Figure "Repair or Replacement of Exhaust Manifold Flowchart" .‪

Figure 2. Repair or Replacement of Exhaust Manifold Flowchart

Section 7.2.2
Removal of Exhaust Manifold

Clean the mounting area between exhaust manifold and cylinder heads, to prevent any foreign material from falling in to the cylinder head exhaust ports.‪

To avoid injury from hot surfaces, allow engine to cool before removing any component. Wear protective gloves.‪

Remove the exhaust manifold as follows:‪

1. Remove the turbocharger. Refer to "6.4.2 Removal of Turbocharger" .
2. Remove the two end bolts and clamps from each end of the exhaust manifold. See Figure "Exhaust Manifold" .
   

   1.Exhaust Manifold Bolt‪	3.Exhaust Manifold‪
   2.Exhaust Manifold Clamps (12)‪	4.Gasket (6)‪

   Figure 3. Exhaust Manifold

3. Install exhaust manifold guide studs, J 34691-A, in each end of the exhaust manifold.
4. Remove the ten remaining bolts and clamps.
5. Remove the exhaust manifold and six gaskets by sliding it over the guide studs.
6. Remove any remaining gasket material from cylinder head.

Section 7.2.2.1
Inspection of Exhaust Manifold

Inspect the exhaust manifold as follows:‪

1. Inspect the exhaust manifold for cracks, stripped mounting bolt threads, or other damage. If any of these conditions is detected, replace exhaust manifold.
2. If any of these conditions are not detected, reuse the exhaust manifold.

Section 7.2.3
Installation of Exhaust Manifold

Install the exhaust manifold as follows:‪

1. Position new exhaust manifold gaskets over guide studs on each end of exhaust manifold. See Figure "Exhaust Manifold" .
   

   1.Exhaust Manifold Bolt‪	3.Exhaust Manifold‪
   2.Exhaust Manifold Clamps (12)‪	4.Gasket (6)‪

   Figure 4. Exhaust Manifold

2. Slide exhaust manifold over guide studs, J-41747, leaving enough room to position the remaining gaskets in place.
3. Using the mounting bolts and clamps to secure the gaskets, position the remaining exhaust manifold gaskets between the exhaust manifold and cylinder head. Tighten the mounting bolts finger-tight.
4. Remove the exhaust manifold guide studs, J-41747, and replace the two remaining clamps and bolts at each end.

   Note: Insure all six mounting gaskets are properly positioned between the exhaust manifold and cylinder head exhaust ports.

5. Torque the bolts to 48-52 N · m (35-38 lb · ft), starting with the center cylinders and working toward the end bolts.
6. Install turbocharger. Refer to "6.4.3 Installation of Turbocharger" .