Koch-Chemie Teerwäsche A "Tea" Bitumen & Tar Remover 1000ml

Break down tar and bitumen with Koch-Chemie Teerwäsche A — no scrubbing

What is Koch-Chemie Teerwäsche A? A solvent-based specialist cleaner built on C10–C13 hydrocarbons that chemically breaks down tar, bitumen, oil and grease residue — neat on a dry surface, 30 seconds to 3 minutes dwell time, then rinse off with a pressure washer. Carries Daimler approval and is free of halogenated hydrocarbons. Not suitable for rubber, EPDM seals, soft plastic trim or freshly sealed paint.

The Koch-Chemie Teerwäsche A is a solvent-based tar and bitumen remover with Daimler approval that lifts stubborn road residue off solvent-resistant surfaces without ever touching the paint mechanically. The active blend — C10–C13 n-alkanes, isoalkanes and cycloalkanes with under 2 percent aromatics — chemically breaks apart the molecule chains in bitumen and tar. The residue runs off in streaks and you either steam it away with the pressure washer or wipe it off with a microfibre cloth.

Free of halogenated hydrocarbons, so it's a lot kinder to materials than the old-school tar removers people kept in jerry cans back in the 90s. Available in 1 litre, 10 litre and 20 litre — plus a 2-pack and 3-pack when you need more. Alongside the alkane blend the formula carries a share of 2-butoxyethanol as a coupling agent, which improves how it wets a glass-smooth panel and keeps it working even at cooler ambient temperatures. For indoor use, run ventilation above three air changes an hour, and eye protection is a must for any overhead work.

• Chemical, not mechanical. You can't polish tar out — scrubbing drags the particles across the paint and leaves swirls behind. Teerwäsche A softens the bituminous residue within 30 to 180 seconds until it flows away or lifts off the cloth in one pass. The brush stays in the drawer.
• Daimler approval as a green light for pro use. Koch-Chemie works hand in hand with the car industry. The Daimler approval isn't a marketing sticker — it means the product is officially cleared for use on Daimler paints and underbody materials. For shops tied to a manufacturer, that's a practical argument.
• Free of halogenated hydrocarbons. Older tar removers often lean on trichloroethylene or perchloroethylene — both heavy on odour, a health concern, and barely approvable for pro use any more. Teerwäsche A works with a modern hydrocarbon blend that's workable in well-ventilated spaces from about 15 °C.

Day-to-day from Detailing1: Teerwäsche A doesn't just break down tar — it strips the wax or sealant underneath along with it. That's the bit manufacturers and rivals rarely mention. If you do nothing after the tar comes off, you're left with unprotected paint that takes on fallout and water spots with no barrier. So always plan it in as the first step of a combo job: tar wash → normal wash with a pH-neutral shampoo → reseal with a spray sealant or wax. For a spot job (the odd tar fleck on the sill) a quick detailer is enough as local protection. For a full exterior job including resealing, set aside about 45 minutes for a mid-size car.

Spray it on neat. Short dwell. Steam it off.

The application is kept deliberately simple. Lay Teerwäsche A on the dry, cold surface undiluted — either straight from the 1-litre bottle with the Canyon spray head CHS-3AN or from a sturdy solvent-safe spray bottle. A wet surface dilutes the solvent and cuts the cleaning power right down — when washing, tar wash first, then shampoo.

Dwell time runs from 30 seconds to 3 minutes — depending on how thick the tar layer is. You can see when it's working: the tar dissolves into brownish-black streaks and runs down vertical surfaces. As soon as that happens, rinse straight off with a strong jet of water or wipe it away with a clean microfibre cloth. A 1000 ml bottle covers roughly 4 to 6 full vehicle sides with moderate tar.

On bigger areas, don't let it dry — in direct sun or on hot paint above 25 °C the solvent flashes off too fast and leaves an oily film that only comes off at the next wash. For underbody or wheel-arch work on commercial vehicles, the 10 or 20 litre version is the right call.

There you apply it over a wide area with a pump sprayer and then steam it off with the pressure washer at around 120 bar. On stubborn, dried-on bitumen spots after a drive through roadworks, a second application does more than a longer dwell on the first pass — the solvent is saturated after about 3 minutes and stops working.

It breaks down tar. And wax too.

Teerwäsche A attacks any organic coating sitting on the paint. That's how it works — and at the same time it's the one catch for anyone who reaches for it without a plan. Carnauba waxes, synthetic polymer-based sealants and most quick detailers dissolve away on contact with the hydrocarbon blend. That's no fault in the product either, it's chemistry: what breaks down bitumen breaks down wax too, because both are built on similar organic molecule structures.

For the real world that means two things. First: every tar wash is followed by a full paint wash with a pH-neutral shampoo to neutralise the solvent residue. Second: the treated spot needs a fresh layer of protection.

If you're only dealing with small flecks on the side sill, you can follow up with a spot wax or detailer. If you're cleaning whole panels or the underbody, build the reseal into the workflow as a fixed step. SiO₂-based ceramic coatings usually aren't fully wrecked after a tar-wash treatment, but they lose noticeable hydrophobicity — a topper or detailer brings them back up to level.

What Teerwäsche A isn't suited to: unpainted soft plastics, rubber seals and EPDM profiles. The solvent swells rubber over longer contact and can dull plastics. It mainly hits window seals, door rubbers and black plastic trim on older vehicles.

Don't spray it over those surfaces broadly — if overspray happens, rinse it off with water within 60 seconds. On fresh wraps and PPF (paint protection film), test first on a hidden spot. Plenty of PPF coatings handle short contact times under 30 seconds but react sensitively to longer exposure.

When Teerwäsche A fits — and when it doesn't

Teerwäsche A is the right call when you're removing genuine road tar, bitumen spray after driving through roadworks, asphalt residue on wheel arches or dried-on oil films in the underbody area. It's also built for the regular cleaning of car-wash brushes and shop floors — wherever it's not paint cosmetics that's needed but real chemical solving power. In the spring season after winter it's standard for underbody prep, once tar-salt mixes have piled up over months.

For insect residue, though, it's not the first choice. Insect proteins are organic but structured differently — enzymatic cleaners like the insect remover work more precisely and more gently on paint there. If you've got both at once — tar on the sill, bugs on the front end — treat both areas separately with the product that fits each. Trying to solve everything with one all-rounder usually ends in more rework. Same goes for tree sap and adhesive residue: both dissolve with the tar wash, but a dedicated tree-sap remover works cleaner.

As for pack size, the 1-litre bottle suits the private user and the occasional detailer planning one go per vehicle. The 2-pack and 3-pack bring the price per litre down by roughly 5 to 15 percent — worth it if there are several vehicles in the household or you want the season's supply locked in.

The 10 and 20 litre drums are trade sizes for reconditioning, underbody cleaning or fleet work — here the outlay only pays off from regular weekly use. For precise single-spot application the 1-litre bottle with the Canyon spray head stays the most ergonomic solution. The spray head delivers a precise cone rather than a mist and doses right onto the problem spot without wetting more area than needed.

Store Teerwäsche A frost-free at room temperature. Once opened, the bottle stays stable for about 24 months as long as the cap is closed tight after use — hydrocarbon solvents evaporate slowly otherwise and the concentration drops.