Cut off main floor, inner longitudinal member and middle crossmember - AR63.40-P-1180-06CW

WARNING: This page is about a different car, the 2011 Mercedes-Benz C300, 2010 Mercedes-Benz C300, 2009 Mercedes-Benz C300, and 2008 Mercedes-Benz C300. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Outer Side Longitudinal Member Spot Welds & Bonded Areas

Courtesy of MERCEDES-BENZ USA

The following operation steps are shown on model 204.0.

Expose spot welds on outer side longitudinal member section (7.1) (areas, A ₁ , A2, B, C, D, E and F).
Drill out Ø 6.7 mm spot welds on outer side longitudinal member section (7.1) (areas A and A 2).
Cut out spot welds on outer side longitudinal member section (7.1) (areas B, C, D, E and F).
Heat outer side longitudinal member section (7.1) in cross-hatched area.
cross-hatched area is bonded.
Remove section from outer side longitudinal member (7.1).
Expose spot welds on offset reinforcement (5) and inner side longitudinal member (6) (areas I and J).
Scribe separation line on offset reinforcement (5) and inner side longitudinal member (6) (areas G and H).
Cut offset reinforcement (5) and inner side longitudinal member (6) at separation line (areas G and H).

Fig 2: Identifying Offset Reinforcement & Inner Side Longitudinal Member Spot Weld Areas & Separation Lines
Courtesy of MERCEDES-BENZ USA

Dimensions:

Do not damage components beneath.
Cut out spot welds on offset reinforcement (5) (area I).
Cut out spot welds on inner side longitudinal member (6) (areas I₁ and J).
Cut out spot welds from rear (area I ₁ ).
Expose spot welds on connection carrier (1), front crossmember (2) and rear crossmember (3) (areas K, L, M, N, O, P and Q).
Cut out spot welds on connection carrier (1), front crossmember (2) and rear crossmember (3) (areas K, L, M, N, O, P and Q).
On model 204.9 cut all MIG solder seams from rear crossmember (3).

Fig 3: Identifying Connection Carrier, Front Crossmember And Rear Crossmember Spot Welds (Areas K, L, M, N, O, P And Q)
Courtesy of MERCEDES-BENZ USA
Heat connecting area (1) in crosshatched areas.
cross-hatched area is bonded.
Remove connecting carrier (1), front crossmember (2) and rear crossmember (3).

Fig 4: Identifying Bonded Area Of Connecting Carrier And Front/Rear Crossmember
Courtesy of MERCEDES-BENZ USA
Scribe separation line on main floor panel (4) along bead (arrows) (area R).
Cut main floor panel (4) at separation point (area R).
Do not damage component below.
Expose spot welds on main floor panel (4) (areas S, U, V, V 1 and W).
Cut out spot welds on main floor panel (4) (areas S, U, V, V 1 and W).
On vehicles with small bracket version in area S, cut resistance spot welds from below.

Fig 5: Identifying Main Floor Panel Spot Welds & Bonded Areas
Courtesy of MERCEDES-BENZ USA

Dimensions:
Drill out Ø 6.7 mm spot welds in main floor panel (4) (area T).
Heat main floor panel (4) in crosshatched areas.
Cross-hatched area is bonded.
Remove damaged main floor panel (4), inner side longitudinal member (6) and offset reinforcement (5).
Perform following step only on vehicles with large bracket version in area S ₁ .
Drill out Ø 6.7 mm spot welds in main floor panel (4) from top (area S ₁ ).

Fig 6: Identifying Main Floor Panel Spot Welds (Area S1)
Courtesy of MERCEDES-BENZ USA

Fig 7: Identifying Main Floor Panel Connection Surfaces (Areas X, Y And Z)
Courtesy of MERCEDES-BENZ USA
Sand down connection surfaces on body to bare metal in cross-hatched areas.
Grind spot weld flanges down to bare metal on both sides.

Observe pretreatment of bonding surfaces (areas X, Y and Z).
Remove shavings.
Coat insides of spot weld flanges with zinc dust paint.
To prevent adhesion problems, do not coat bonding surfaces with zinc dust paint (areas X, Y and Z).