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

Removing Tar and Bitumen with Koch-Chemie Tar and Bitumen Remover A without Scrubbing

What is Koch-Chemie Tar and Bitumen Remover A? A solvent-based special cleaner based on C10–C13 hydrocarbons, which chemically dissolves tar, bitumen, oil, and grease residues — apply neat to a dry surface, leave to dwell for 30 seconds to 3 minutes, then rinse off with high pressure. Daimler approved and free from halogenated hydrocarbons. Not suitable for rubber, EPDM seals, soft plastic add-on parts, and freshly sealed paint surfaces.

The Koch-Chemie Tar and Bitumen Remover A is a solvent-based tar and bitumen remover with Daimler approval, which dissolves stubborn road residues on solvent-resistant surfaces without mechanically stressing the paint. The active ingredient – a mixture of C10–C13 n-alkanes, isoalkanes and cycloalkanes with less than 2 percent aromatics – chemically dissolves the molecular chains of bitumen and tar. The residues run off in streaks and can be steamed off with a high-pressure cleaner or wiped off with a microfiber cloth.

Free from halogenated hydrocarbons and thus significantly more material-compatible than many classic tar removers from workshop canisters of the 90s. Available in 1 liter, 10 liter, and 20 liter – plus a 2-pack and 3-pack for multiple needs. In addition to the alkane mixture, the formulation contains a proportion of 2-butoxyethanol as a solvent, which improves wetting on smooth paint surfaces and keeps the product working even at cooler workshop temperatures. For use in enclosed spaces, ventilation with more than 3 air changes per hour is recommended, and eye protection is mandatory for overhead work.

• Chemical instead of mechanical. Tar cannot be polished – scrubbing drags the particles across the paint and leaves swirls. Tar and Bitumen Remover A softens bituminous residues within 30 to 180 seconds to such an extent that they run off or are absorbed by a cloth in one go. You no longer need to use a brush.
• Daimler approval for workshop use. Koch-Chemie works closely with the automotive industry. Daimler approval is not a marketing label – it means that the product has been officially approved for use on Daimler paints and underbody materials. A pragmatic argument for workshops with manufacturer ties.
• Free from halogenated hydrocarbons. Older tar removers often rely on trichloroethylene or perchloroethylene – both are highly odorous, health-relevant, and hardly approved for workshop use anymore. Tar and Bitumen Remover A works with a modern hydrocarbon mixture that can be used in well-ventilated rooms at temperatures of around 15 °C or above.

Practical Tip from Detailing1: Tar and Bitumen Remover A not only dissolves tar – it also dissolves the wax or sealant underneath. This is the point that manufacturers and competitors rarely mention. If you do nothing after tar removal, you will have unprotected paint that will be affected by rust film and water spots without a barrier. Therefore, always plan its use as the first step in a combined treatment: Tar wash → normal wash with pH-neutral shampoo → re-seal with spray sealant or wax. For spot application (individual tar splashes on the sill), a quick detailer is sufficient as local protection. For a complete exterior treatment including re-sealing, allow about 45 minutes for a mid-range car.

Spray on neat. Let it dwell briefly. Steam off.

The application is intentionally kept simple. Apply Tar and Bitumen Remover A undiluted to the dry, cold surface – either directly from the 1-liter bottle with the Canyon spray head CHS-3AN or from a robust workshop spray bottle. A wet surface dilutes the solvent and significantly reduces the cleaning effect – when washing, apply the tar remover first, then the shampoo.

The dwell time is 30 seconds to 3 minutes – depending on the thickness of the tar coating. You'll see when the product is working: the tar dissolves into brownish-black streaks and runs off vertical surfaces. As soon as this happens, rinse immediately with a strong stream of water or wipe off with a clean microfiber cloth. One 1000 ml bottle is sufficient for about 4 to 6 complete vehicle sides with moderate tar contamination.

Do not let it dry on larger areas – in direct sunlight or on hot paint above 25 °C, the solvent evaporates too quickly and leaves an oily film that only disappears with subsequent washing. For underbody or wheel arch treatment on commercial vehicles, the 10 or 20-liter version is the right choice.

There, it is applied over a large area with a pressure sprayer and then steamed off with a high-pressure cleaner at approximately 120 bar. For stubborn, dried-on bitumen stains after a construction site drive, a second application helps more than a longer dwell time during the first pass – the solvent is saturated after about 3 minutes and will not work further.

It dissolves tar. And wax, too.

Tar and Bitumen Remover A attacks every organic coating on the paint. This is its operating principle – and at the same time its only drawback for users who apply it without prior planning. Carnauba waxes, polymer-based synthetic sealants, and most quick detailers dissolve on contact with the hydrocarbon mixture. This is not a product defect, but chemistry: what dissolves bitumen also dissolves wax, because both are based on similar organic molecular structures.

In practice, this means two things. First: every tar removal is followed by a complete paint wash with pH-neutral shampoo to neutralize solvent residues. Second: the treated area needs a new protective layer.

If you're only treating small splashes on the side sill, you can follow up with a spot wax or detailer. If you're cleaning entire panels or the underbody, plan for re-sealing as an integral part of the workflow. Ceramic coatings based on SiO₂ are usually not completely damaged after a tar removal treatment, but their hydrophobicity is noticeably reduced – a topper or detailer brings them back up to par.

Tar and Bitumen Remover A is not suitable for unpainted soft plastics, rubber seals, and EPDM profiles. The solvent swells rubber with prolonged contact and can dull plastics. This particularly affects window seals, door rubbers, and black plastic add-on parts on older vehicles.

Do not spray extensively on these surfaces – if overspray occurs, rinse with water within 60 seconds. On fresh wraps and PPF (paint protection film), test in an inconspicuous area beforehand. Many PPF coatings tolerate short contact times under 30 seconds but are sensitive to prolonged exposure.

When Tar Remover is suitable and when it is not

Tar and Bitumen Remover A is the right choice when real road tar, bitumen splashes after driving through a construction site, asphalt residues on wheel arches, or dried oil films in the underbody area need to be dissolved. It is also designed for regular cleaning of car wash brushes and workshop floors – where true chemical dissolving power is required rather than paint cosmetics. In the spring season after winter, it is standard for underbody preparation when tar-salt mixtures have accumulated over months.

However, it is not the first choice for insect residues. Insect proteins are organic, but structured differently – for this, enzymatic cleaners like the insect remover work more precisely and are more paint-friendly. If you have both – tar on the sill, insects on the front – treat both areas separately with the appropriate product. Trying to solve everything with an all-rounder usually results in more rework. The same applies to tree resin and adhesive residues: both dissolve with the tar remover, but a specialized tree resin remover works more cleanly.

For private users and occasional detailers who plan one application per vehicle, the 1-liter bottle is recommended. The 2-pack and 3-pack reduce the price per liter by about 5 to 15 percent – useful if there are several vehicles in the household or if the supply for the season needs to be secured.

The 10- and 20-liter canisters are workshop containers for detailing, underbody cleaning, or fleet operations – here, the purchase is only worthwhile for regular weekly consumption. For precise spot application, the 1-liter bottle with a Canyon spray head remains the most ergonomic solution. The spray head delivers a precise cone instead of a mist and targets the problem area without unnecessarily wetting a larger surface.

Tar and Bitumen Remover A should be stored at room temperature, protected from frost. The bottle remains stable for about 24 months after opening, as long as the cap is tightly closed after use – otherwise, hydrocarbon solvents slowly evaporate, and the concentration decreases.