Replace the rivet nuts in the exhaust manifold. - AR49.10-P-5531-01GZ

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Fig 1: Identifying Cocking Bolt (103 589 01 39 00)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Hammer rivet nuts with a suitable bolt (arrow) out of exhaust manifold bores.
Before doing so, manually screw the bolt into the rivet bushes.

Fig 2: Locating Rivet Nuts
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Insert new rivet bushes into exhaust manifold bore.
Screw in cocking bolt and tighten.
Unscrew cocking bolt.

Fig 3: Identifying Cocking Bolt
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.