Automotive fluids are rather gross and toxic, and brake fluid is among the worst of them. Glycol-based brake fluid (DOT 3 or 4), used in the vast majority of cars, can act like paint thinner if spilled, causing lasting damage in as little as five minutes. It was not a good day when my Honda PC800’s hydraulic clutch, which used glycol brake fluid, sprang a leak all over the bike’s rare unobtainium bodywork.
Fortunately, if you know what to do and act quickly, you can avoid permanent paint damage. Drop everything, clean it up immediately, and you can save your paint job. If you wait five minutes or more, the brake fluid will start eating the clear coat and paint, leaving visible marks. The longer you wait, the worse the damage gets, until about 30 minutes after the spill. You don’t need any fancy cleaners that may or may not work, either. Just paper towels, soap, and water will do.
Time is of the essence
It’s easy to spill brake fluid when filling or topping off your brake fluid reservoir, perhaps while bleeding your brakes (and you don’t need a specialized tool to bleed the brakes). Fortunately, the paint on any metal below the reservoir won’t be visible from outside the car, but it’s still important to clean up the spill quickly to avoid damaging the paint, exposing bare metal, and inviting rust.
Take a moment to put on some gloves. If brake fluid can damage paint this badly, it’s no good for human skin either. Dab the spill area with paper towels to absorb as much spilled fluid as possible. Do not wipe! This will spread the fluid over an even wider area, and we’re trying to contain it as much as possible.
Once you’ve soaked up as much brake fluid as you can, clean the area with soap and water. You can wipe it with a rag or sponge soaked in soapy water, or spray the area and wipe it up with a dry towel. Finally, rinse the area with clean water to remove any remaining residue. If you’ve acted quickly enough, congratulations — you’ve saved your paint from permanent damage.
