Prepare Rear Longitudinal Member For Installation - Ar64.20-P-1200-23MFC

Model 177.1/9 

with code U54 (Compound-link axle) 

except code U55 (Multi-link axle) 

The following operation steps are shown on the left side of the vehicle. In case of damage on the right side of the vehicle, these steps must be performed analogously.

The superordinate service document as well as the safety information in the service document must be observed..

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1. Mark separating point on rear seat reinforcement(3) and separate (area A).

   Transfer separating point from vehicle.

2. Grind mating surface on rear seat reinforcement(3) down to bare metal in cross-hatched area.
3. Remove grinding dust.
4. Apply zinc dust paint in the cross-hatched area onto connecting flanges that are no longer accessible after installing side roof paneling.

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5. Grind mating surfaces on the cover(4) down to bare metal in the cross-hatched areas.
6. Remove grinding dust.

   Observe pretreatment of bonding surfaces.

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7. Install covers (5.1, 5.2) on rear longitudinal member (1), fit, and fix in place.
8. Mark position of cover(5.1) relative to cover(5.2).
9. Remove covers (5.1, 5.2).
10. Grind covers (5.1, 5.2) down to bare metal on both sides and coat the insides with zinc dust paint (area D).
11. Align cover(5.1) to cover(5.2) at the marked position and fix in place.
12. Covers (5.1, 5.2) (area D).

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13. Grind mating surfaces on the covers (5.1, 5.2) down to bare metal in the cross-hatched areas.
14. Remove grinding dust.

    Observe pretreatment of bonding surfaces.

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15. Grind mating surfaces on the rear longitudinal member (1) down to bare metal in the cross-hatched areas.
16. Remove grinding dust.
17. Apply 2-component adhesive in cross-hatched areas to the rear longitudinal member (1) (areas B₁ and B₂ ).

    Observe pretreatment of bonding surfaces and manufacturer's specifications for drying and processing time of 2-component adhesive.

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18. Assemble rear longitudinal member (1) and covers (5.1, 5.2), fit, and fix in place.
19. Rear longitudinal member (1) and covers (5.1, 5.2) (areas C₁ , C₂ , C₃ , C₄ , C₅ and C₆ ).
20. Drill out rivets on spring mount (1.1) with a diameter of 6.5 mm (areas E₂ ).
21. Remove spring mount (1.1).

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22. Rear longitudinal member (1) (areas E₃ ).
23. Surface grind plug spot welds on the rear longitudinal member (1) (areas E₃ ).

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24. Grind mating surfaces on spring mount (1.1) down to bare metal in cross-hatched areas on inside.
25. Remove grinding dust.

    Observe preliminary treatment of bonding surface.

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