Formulation Card
FC-13.4-M
Wheel Cleaner — Acidic, Multi-Metal Safe
mediumSource: Chapter 13 §13.2
Ingredients
| Ingredient | % w/w | Function |
|---|---|---|
| Deionized water | qs to 100.0 | Diluent |
| Phosphoric acid (75%) | 8.0 | Acid builder, iron oxide dissolution |
| Nonionic surfactant (AE, , 6 EO) | 3.0 | Wetting, penetration |
| Oxalic acid | 1.5 | Chelant, ferric ion complexation |
| Benzotriazole (BTA) | 0.3 | Corrosion inhibitor for Al/Cr |
| Hydroxyethyl cellulose | 0.4 | Thixotropic thickener, dwell time |
| d-Limonene | 0.5 | Solvent, tar removal |
| Colorant (purple, iron-reactive) | 0.01 | Visual indicator |
| Total | 100.0 |
Formulation Notes
Acid-based brake dust remover with corrosion inhibition for aluminum, chrome, and clear-coated wheels.
Method: Add phosphoric acid to water slowly with cooling (exothermic). Dissolve oxalic acid. Add nonionic surfactant and d-limonene. Disperse hydroxyethyl cellulose with high-shear mixing. Dissolve BTA in a small amount of warm water and add last. Properties: pH 2.5–3.5, viscosity 1{,}500–3{,}000 cP. Use: Spray on cool, wet wheels; dwell 60–90 seconds; agitate with brush; rinse thoroughly. Never allow to dry on the surface . The color change to purple upon reaction with ferrous brake dust provides visual feedback that the chemistry is active .