Body - Applying PVC Undercoating and Seam Sealer

86MERCEDES02
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS

DATE: September 1986 REF.NO. 97/15


SUBJECT: APPLYING PVC UNDERCOATING AND PVC SEAM SEALER DURING REPAIRS


This subject deals with the proper removal and application of PVC undercoating and PVC seam sealer.

WARNING! Do not burn off PVC material. A highly corrosive hydrochloric acid is formed when burning PVC material, i.e. when ignited with a welding torch or other heat source.

A new application of PVC material will not adhere to the burnt one, and consequently will promote rust under the surface.

For reasons stated above, the proper removal of PVC undercoating and PVC seam sealer from either chassis or body sections is done by means of a rotary wire brush or a heat gun (hot air) and scraper. This prevents the development of noxious fumes and gases, which are dangerous when highly concentrated.

CAUTION! When working with a rotary wire brush, the use of proper eye
protection is required.

All areas to be treated with PVC undercoating or PVC seam sealer should be thoroughly cleaned (if possible by using a steam cleaner) and dried. All wax, oil, and grease residues as well as any loose PVC material should be removed, in particular from areas where the new PVC material will meet the old material. Any rusted or corroded spots should be ground to the bare metal.