Fish finder

[Brian Cope]

I have a depth sounder but would like to add a fish finder as I like to fish and see contours below. I'm trying to figure out how to install transducer, as they seem to screw in and I really don't want to put screw holes in the fiberglass at or below the waterline. I'd like to do it without hauling out if possible.

79' Cal 39

[kayakerChuck]

As long as your boat does not have a cored hull, you should be able to use an in hull transducer. I have one something like this, and it works great. https://shop.hamiltonmarine.com/prod...kaApRHEALw_wcB

They come is many styles, so be sure to get one that's appropriate to your unit and use.

I also have a fancy Garmin downscan transducer stuck in a block of buytl tape in my bilge. It was just to see if it would work. It work so well, that 2 years later I have not changed anything.

[skipperpete]

My boat has the Raymarine airmar transducer as in KayakerChuck’s post and like you, I wanted more than just the numbers display so I bought a new plotter sounder. I was considering putting the new transducer in the existing airmar internal tank but the instructions said to just glue it to the hull with slow epoxy glue which I eventually did after testing the location with the transducer in a plastic bag full of water (thanks CF members for the tip). Having confirmed that it all worked I removed the bag and left the transducer sitting in the dry bilge and even before the epoxy it was still reading the exact depth and showing the resident school of fish as they did the feeding circuit.

[SailingHarmonie]

Originally Posted by Brian Cope

I have a depth sounder but would like to add a fish finder as I like to fish and see contours below. I'm trying to figure out how to install transducer, as they seem to screw in and I really don't want to put screw holes in the fiberglass at or below the waterline. I'd like to do it without hauling out if possible.

79' Cal 39

A transom mounted transducer, which sounds like what you are looking at, is a bad choice for a sailboat.

I am sure your Cal has a solid FRP hull so you have a choice. Either a through-hull model or an in-hull model. Airmar makes almost all the transducers for the major brands, the only difference being the kind of connector on the end of the wire.

If you don't want to put a hole in your boat, the Airmar P79 in-hull transducer is a great choice. You can install it with the boat in the water without an issue.

If you are putting a hole in the hull, there are a LOT of choices that depend on the model fishfinder you have and how deep your pockets are. We have a Simard S2009 that is a great dedicated display. It has put us on a lot of fish over the years.

[Brian Cope]

do the through hulls go in the bilge in front of the keel near the mast?