PD-0120: Metal Parts Prep - E-Coat Primer

Most Original Equipment Manufacturer (OEM) parts come from the factory with a primer called e-coat. E-coat stands for Electro-deposition Coating. The part is dipped into a primer bath and the e-coat adheres to the part with the help of an electrical process. E-coat is a very durable and corrosion resistant coating so it should not be removed from the part. Most e-coat appears to be a glossy black coating.


Step-by-Step Instructions

  1. Review work order to ensure that all parts to be painted are present and repairs are understood.
  2. Inspect part for imperfections and damage. Determine what repairs should be made if any (follow all process documents for repairs made to the part)
  3. Clean entire part thoroughly with Wax & Grease Remover and/or SWX350 waterborne cleaner and a clean towel. Dry thoroughly to ensure there is no leftover residue.
  4. To determine if E-coat is stable:
    Test by rubbing e-coat with thinner or urethane grade solvent on a clean towel. If coating wipes off or softens significantly, it must be removed by sanding. Apply approved bare metal primer to ALL exposed bare metal areas.
    If e-coat is stable, proceed to next step.
  5. Electrodeposition Primer must be thoroughly cleaned and may then be directly overcoated with Sealer in a wet-on-wet application without abrading.
    1. To remove minor defects – Lightly sand primer with a DA sander with 400 grit and an interface pad. Remove as little e-coat as possible.
    2. If preferred, on edges, body lines and recessed areas, use a hand scuff pad.
  6. Re-clean entire part thoroughly with Wax & Grease Remover and/or SWX350 waterborne cleaner and a clean towel. Dry thoroughly. Tack off the dry part before Primer Sealer application.
  7. Primer Sealer must be applied to e-coat. Obtain primer sealer gray shade number (G1-G7) from color formula retrieval screen. Apply medium wet coat of primer sealer to entire part.