How to apply Foulfree

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


Surface Preparation

🕭 Gloves and protective glasses must be worn at all times.


🕭 For plastic fairing blocks (polyethylene, polypropylene, nylon etc.), you may need an adhesion promoter—adhesion promoter is not included in this kit. WARNING: Do NOT use adhesion promoter on transducer housings, bodies or face. Adhesion promoters contain solvents which can destroy the transducer and void the manufacturer’s warranty.


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 - Apply an adhesion promoter to plastic fairing blocks before the transducer is installed when possible (adhesion promoter sold separately).

  1. Abrade the fairing block with the abrasive pad provided.
  2. Remove any residue from sanding
  3. Apply the adhesion promoter to the Fairing block ONLY, following the instructions recommended by the manufacturer.
  4. For existing installs: Tape over the entire transducer face and edges. Ensure the entire transducer face is covered, as the adhesion promoter does have adverse effects on the urethane face. Also tape off any areas that you do not wish to coat with the adhesion promoter.
  5. Once the adhesion promoter has been applied and dried, remove the tape from the transducer body or face.

WARNING: Do not let any of the adhesion promoter make contact with the urethane transducer face.  Damage will occur and will void manufacturer’s warranty


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 XD Clean wipe provided. Immediately remove any residue with a clean, dry rag. Ensure the surface is 100% clean and dry before proceeding.



1. Squeeze FOULFREE™ Transducer Coating onto the provided application brush.


2. Gently apply one thin coat to the surfaces that you want to protect from fouling.


3. Make sure there are no heavy runs or sags. You’ll have 5 to 10 minutes to touch these up.


Dry Time

FOULFREE™ requires a minimum of 8 hours to dry before launching. In colder conditions, 40–60℉ (5–13℃), 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. 

Foulfree Safety Documents

Foulfree Technical Documents

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