BMW 7 Series: Straightening Aluminium Components In Structure

• Reshaping or heating extruded sections and cast parts is not permitted! Failure to comply with this requirement would have the following results:
  In the case of reshaping, weld seams (E52) or glued connections (E60, E61, E63, E64) tear in the surrounding area.

  In the case of reshaping, the material loses up to 40 % of its original strength.

  In the case of heating, the material loses up to 40 % of its original strength.

  The adhesive is destroyed at temperatures =120ºC (E60, E61, E63, E64).

  Extruded sections and cast parts which show visible or measurable signs of deformation must be replaced.

  Perform the check for deformation with the aid of the straightening system.

  For optical testing, strip adjoining components in cases of doubt.

  Extruded sections are used in the E52 as engine supports, door pillars, side members, etc.

  Extruded sections are used in the E60, E61, E63, E64 as engine supports.

  Cast parts are used in the E60, E61, E63, E64, E70, E71 as spring supports.

• Reshaping of extruded sections and cast parts may only be used to achieve optimum joining of connecting faces (e.g. when bulkhead is damaged). Reshaped parts must be replaced.
• Repairs which affect the mounting points of mechanical assemblies and chassis components must be carried out on the straightening bench. Use the vehicle-specific straightening attachment set or vehicle-specific data sheet.

  Straightening attachment supports and data sheets are also available for the top section, e.g.: door pillars, convertible top mounts, cowl, rear lid hinges, etc.

• Check windshield and rear window apertures for curvature by inserting the original glass.
• Take the gap dimensions for doors, engine hood and rear lid from the vehicle-specific gap dimension diagram.
• Exceptions on the E60, E61, E63, E64:
  Carrier support and bulkhead may be straightened if they do not have any cracks, sharp-edged damage or holes. After repair work, check parts again for cracks.

  Examine adjoining adhesive flanges for peeling off. If necessary, seal and preserve with SEALING COMPOUND.

  Observe the frame alignment control dimensions for the carrier support.

  Any repairs to the bulkhead if cracked outside the approved repair scopes are only permitted after consultation with and approval by BMW. Should you have any questions, please contact the country-specific Hotline.

STRAIGHTENING ALUMINIUM PARTS ON OUTER SKIN

1.0 Recommended tools

• Use only those tools specially intended for aluminium repairs (refer to Service Information 5 03 03 975).
• Do not use any tools that have already been used for steel repairs (contact corrosion).
• Do not use any sharp-edged tools (notch effect).

2.0 Straightening outer shell

• "Cold" straightening: Press dents out from their center and smooth in an outwards direction with gentle taps.

  In the case of small, soft dents (hail and parking damage), this is also possible without damaging the paintwork. This work requires a special tool (refer to Service Information 5 04 98 328) and a trained worker.

• "Hot" straightening: Heat dents in their central point only with a gas flame or hot air blower. Then quench the material with a wet cloth. Heating can only be detected by warpage of the material. The color of the paint does not change.
• In the case of damaged areas which are only accessible from one side, stud welding can be used (refer to Service Information 5 01 00 532). The aluminium stud welded on in the center of the damaged area is beaten out with a hammer until the dent is eliminated. The stud is then ground off.
• Avoid notching and cracking.
• Avoid hardening and overstretching.
• Avoid heating and overheating the outer shell over large areas.

STRAIGHTENING STEEL COMPONENTS IN THE STRUCTURE

• High-strength and super-high-strength steel plates as a rule cannot be reshaped. Reshaping only serves as a preparatory measure to replacing the component in order to achieve optimal joining of the connection points.
• Bearing body components such as e.g. engine supports, door pillars, side members etc. with deformations which can no longer be returned to their original shape by "cold straightening" must be replaced.

  Heating bearing body components for better reshaping is not permitted! Failure to comply with this requirement would result in a loss of original strength of up to 40 %.

• The body must be anchored as follows for reshaping:
  If using vehicle-specific/universal straightening attachment sets (Carbench/Celette/Car-O-Liner), it is necessary to secure the body additionally with 4 retaining clips to the spot flange of the entrance or to the 4 jacking points. The spot flange (if available) is to be preferred.

  If using universal electronic or mechanical straightening systems (Car-O-liner/Celette), it is necessary to secure the body with 4 retaining clips to the spot flange of the entrance or to the 4 jacking points. The spot flange (if available) is to be preferred. In addition anchor at least 2 points with the securing set.

  Failure to comply with these instructions will result in damage to the body during reshaping in non-damaged areas. Vehicle-specific straightening attachments and universal mounts may be damaged.

• Repairs affecting the mounting points of assemblies and chassis/suspension components must be carried out on the straightening bench with the matching straightening attachment set or specification sheet for the vehicle.

  Straightening attachments and specification sheets are also available for the top section, e.g.: door pillars, convertible top mounts, cowl, rear lid hinges, etc.

• Check windshield and rear window apertures for curvature by inserting the original glass.
• Take the gap dimensions for doors, engine hood and rear lid from the vehicle-specific gap dimension diagram.

STRAIGHTENING STEEL PARTS ON OUTER SKIN

1.0 Recommended tools

Only use those tools designed for steel repairs.

2.0 Straightening outer shell

• "Cold" straightening: Press dents out from their center and smooth in an inwards direction with gentle taps.

  In the case of small, soft dents (hail and parking damage), this is also possible without damaging the paintwork. This work requires a special tool (refer to Service Information 5 04 98 328) and a trained worker.

• "Hot" straightening: Heat dents in their central point only with a gas flame until bright red hot. Then quench the material with a wet cloth.
• Stud welding can be used in the case of damage where access is only possible from one side. Weld on the stud in the middle of the damaged area. The steel pin or shim is driven out using a hammer until the depression is removed. The stud, pin or shim is then ground or twisted off.
• Avoid cracking.
• Avoid hardening and overstretching.
• Avoid heating and overheating the outer shell over large areas.
• If, after steel parts have been straightened, the surface shows no dents larger than 2 mm, these dents may be touched up with knifing filler.

  Dents larger than 2 mm must be treated with filling solder.

NOTE: Only applicable within the European Union! European used-car regulations prohibit the use of tin containing lead in motor vehicles introduced after 01.07.2003!

• For safety vehicles, follow the special notes and information in the repair instructions.

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