[CA] Install help needed for a CPT 110 Transducer

[BForsyth]

Hi all,

Looking to install a CPT-110 thru hull down vision transducer with plastic fairing block on my 1998 Carver 400 CMY this weekend.

Was wondering if someone could shoot me off tips and tricks for install. Is there a video for this? Cant really find one online that shows an install with a fairing block. Ive read thru the instructions.... got a few questions.


1. Can the fairing block be cut with a table saw instead of a band saw? I don't own a band saw.

2. Should I use 3M 4200 or 5200 adhesive for the job?

3. When drilling the [censored]..... Should I be drilling straight up into the boat perpendicular to the water line or straight into the boat so more like an angle? I believe my dead rise is 17 degrees.

4. Do I run silicone between the transducer and the bottom fairing block? Or just between the bottom fairing block and the bottom of the hull?

Thanks for the help!

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum BForsyth,

Q1. Can the fairing block be cut with a table saw instead of a band saw? I don't own a band saw.
A1. Please see a video found here showing a transducer fairing block being cut. I believe that may find it more challenging, potentially more dangerous, and will generate a larger kerf than that produced by a bandsaw. Should you not have a bandsaw of adequate size, then may want to consider contacting a marine electronics installer to cut the fairing block for you.

Q2. Should I use 3M 4200 or 5200 adhesive for the job?
A2. The installation instructions simply specify "Marine grade adhesive sealant (suitable for submerged applications)". 3M 4200 and 5200 are two adhesives designed for such purposes.

Q3. When drilling the [censored] ..... Should I be drilling straight up into the boat perpendicular to the water line or straight into the boat so more like an angle? I believe my dead rise is 17 degrees.
A3. Should the fairing block be properly cut, then it will cause the transducer's shaft to be perpendicular to the waterline and for the transducer's face to be parallel to the waterline.

Q4. Do I run silicone between the transducer and the bottom fairing block? Or just between the bottom fairing block and the bottom of the hull?
A4. See the response to Q2. The same sealant may be used for all sealing aspect's of the transducer's installation.

[BForsyth]

Thanks for the quick response.

Another question. What size [censored] saw should I use?? Instructions don’t say.

[Chuck - Raymarine - Moderator]

BForsyth,

Per Chapter 3.5 Tools required of the DownVision Thru-Hull Transducers CPT-70 / CPT-80 / CPT-110 / CPT-120 Installation Instructions, a 32 mm (1 1/4 in) [censored] cutter is required to accommodate the transducer's shaft.

[BForsyth]

Thanks!

Ok.... Another quick Question. The instructions don't say anything about bottom paint. Do I need to sand away any bottom paint around the area where the transducer will be?

[Chuck - Raymarine - Moderator]

BForsyth,

As indicated within my response to your earlier question, the transducer fairing block and transducer will be sealed to the hull using "Marine grade adhesive sealant (suitable for submerged applications)". Such sealants typically require that the surface be prepped to ensure that they are clean, free of paint, grease, or oils, and possibly lightly sanded. It is recommended that the instructions provided by the manufacturer of the the chosen sealant be referred to when seeking information for preparing the surfaces which will be sealed.

[BForsyth]

As I thought! Thanks.

[Chuck - Raymarine - Moderator]

You're welcome.