Body noises - General - RA94001290100X(94-100)
| Commercially available tools | Order number | e.g. company |
|---|---|---|
| Flow tester for air | CH 216 | Dragerwerke D-2400 Lubeck or Auer-Gesellschaft D-1000 Berlin |
Body noises can result from various causes. The remedies listed are general instructions and additional work may be required from case to case.
| Cause | Remedy |
|---|---|
| Noises at welded joints | |
| Loose welds (metallic knocking) | Bend flanges apart slightly and oil, caulk if required.
NOTE:
If a number of spot welds along a seam are loose check in detail and repair, if required.
|
| Paint cracking noises | |
| Cracks in paint at transitions, joints between body parts due to body twisting | Treat joints by coating lightly with sliding agent, part no. 000 989 26 58. After evaporation of the solvent a permanent wax film forms even in small gaps. In special cases oil, avoid soiling. |
| Noises from foam parts | |
| Foam parts touch and rub against one another or against other parts. | A permanent gap must be created at the contact points between the foam parts, e.g. insert resilient material (felt strips, part no. 000 983 17 10). When installing foam parts, coat foam part surface in contact with body (rear side) with sliding agent, part no. 000 989 26 58 (this applies to foam parts which are removed and reinstalled as well as to new parts). |
| Rubber noises | |
| The rubber seals on doors and trunk lid rub against the contact surface. | Check door clearance, adjust if required. Check sealing frame, replace or clean as required and coat with talcum powder. Check and clean sealing frame contact surfaces with body. |
| Wind noises | |
| At high speeds wind noises can occur on body parts at which the air flowing by is diverted. An air vortex can also form in a cavity. Such hollow cavities (sack formation) can occur when a rubber gasket does not make full contact in a small area. Moreover, leaks, e.g. along the door sealing frame, can cause wind noises. | These leaks can be detected more easily by using smoke from a flow test tube. To perform this test close doors, windows and sun roof, if present, and switch the heater fan to the highest speed to create pressure. Hold smoke tube close to suspected areas and have assistant check the smoke escaping on the outside. Ensure that individual parts are properly installed. |
| Whirling noises At certain engine or vehicle speeds whirling noises can occur far away from the actual source of the noise due to transmission of the vibration. This must be taken into consideration when attempting to locate the source of the noise. |
Fasten vibrating control cables to present lines with cable strap. |
| Sheet metal noises Body torsion can cause noises at contacting sheet metal parts. |
|
| Foreign body noises | |
| Foreign bodies present in cavities. | Establish location of foreign body and - as far as possible - remove or eliminate noise by applying adhesive such as MB universal sealing compound or similar to foreign body. Appropriate material can be applied through openings already present in the hollow cavity. In special cases additional holes may be necessary, which must be treated and plugged with appropriate plugs afterwards.
NOTE:
Always determine where the foreign body came from and reinstall missing parts if applicable.
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