How to apply Foulfree

Keep your transducer signal clear with Foulfree, the best foul-release technology on the market.



šŸ•­ Gloves and protective glasses must be worn at all times.


šŸ•­ For better adhesion of Foulfree™ Transducer Coating on plastic fairing (polyethylene, polypropylene, nylon, etc.), you may need to use a piece of 40 grit sandpaper—NOT included. Do NOT sand the transducer housing or face as it will damage the transducer, voiding the manufacturer’s warranty.

Surface Preparation


Transducer in service:

Remove fouling and/or any previous coatings from the transducer housing and face with the abrasive pad provided.


  • In case of heavy fouling, scrape transducer face with a metal putty knife without gouging the surface. Drag the putty knife across the transducer face at a perpendicular angle and follow with a wet sanding block. Never use a power sander or pressure washer on the face of the transducer. 


Take care not to scratch or damage the transducer face.


Fairing blocks ONLY – To improve adhesion between plastic fairing blocks and the Foulfree™ coating, we recommend sanding the fairing block with 40 grit sandpaper – sold separately.

  1. Abrade the fairing block with 40 grit sandpaper to achieve a roughened surface.
  2. Remove any residue from sanding

Transducer Face & Housing:

  1. Lightly scuff/abrade plastic housing and face of the transducer.  Do not scour or deeply scratch the face of the transducer.
  2. Tape off any areas you do not wish to coat with the Foulfree™ Transducer Coating.
  3. Clean the transducer face with the XDclean wipe provided. Immediately remove any residue with a clean, dry rag. Ensure the surface is 100% clean and dry before proceeding.
Diagram of transducers and their components

Abrasive Pad



Clean the surface to be coated with our specialized cleaning wipe. XDclean is transducer safe and helps to improve adhesion between the Foulfree™ coating and the transducer.

Remove any residue with a clean, dry rag.


XD Clean


Applying Foulfreeā„¢

We have included a small, high quality brush to provide the best result.

Pierce the seal of the tube using the lid. Squeeze a small amount of the Foulfree™ coating directly on to the brush.

Apply a thin layer of the coating on to the transducer. The idea thickness is between 50 and 100 microns. Make sure there are no heavy runs or sags. You will have 5 to 10 minutes to touch these up.


Applying Foulfree


Dry Time


Foulfree™ requires a minimum of 8 hours to dry before launching. In colder conditions, 40–60°F / 5-13°C, wait at least 24 hours before launching.


Foulfree™ can sit out of water for extended periods of time in warm or cold climates with no adverse effects. 



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