Existing transducer...

garyf · Posted: Tue Aug 18, 2020 8:29 pm Post subject: Existing transducer...

I've got an existing thru-hull transducer below the helm - it's not compatible with new electronics, so not going to use it.

Should I just leave well enough alone... or is there a compelling reason to remove it and repair the area? If it should be replaced, am I correct in assuming it's not a high priority item as long as it's not leaking and it doesn't show signs that the core is compromised?

Thanks for any input.

tsturm · Posted: Tue Aug 18, 2020 10:42 pm Post subject: Re: Existing transducer...

thataway · Posted: Tue Aug 18, 2020 11:02 pm Post subject:

Is this a 'Shoot thru the hull" (if so the core has been removed and there is solid glass between the transducer face and the water. If it is a tru thru hull and a flush mount, it would be probably OK to leave, at least for now. If it is a transducer which is external to the hull then I would probably remove it.

It is possible that this transducer may not be comparable with your modern chart plotter (Frequencies, CHIRP, Down scan etc). Agree that Airmar should be contacted and ask about the specs of this transducer (IF you can ID it).

Is the cable intact, or has the wire been cut. This may make a difference in usability.

garyf · Posted: Tue Aug 18, 2020 11:57 pm Post subject:

I can actually see the transducer on the outside, so not a shoot through if I'm understanding properly (and I think I am because there's a good example of installing a shoot through in the photo library).

Cables are still attached if I recall correctly (not near the boat at the moment).

I think my dad wasn't happy in some way with it because there is a brand new, uninstalled transducer in a box amongst his stuff. His old (OLD!) finder was a Furuno and as far as I can tell from the docs, he planned to use the new transducer with the old finder.

Airmar is a great lead, I had no idea they made all of the transducers - I'll go down that hole a bit.

thataway · Posted: Wed Aug 19, 2020 3:09 pm Post subject:

what is the size of the transducer outside and the "stem" inside? This will help to determine if this can be easily replaced. The question is was a "doughnut" of thickened epoxy made in the routed out core around where the transducer was placed thru the hull--both to protect the balsa core, and to take compression from the nut on the stem as it is tightened.

What brand of chartplotter/sonar/Radar MFD are you going to get? That will determine what functions the transducer can utilize. Also although there can be an argument for a forward mounted transducer when going slow-there it may or may not read well when on a plane, because of turbulence of the water this near to the bow. Most C Dorys use a transom transducer.

garyf · Posted: Wed Aug 19, 2020 3:29 pm Post subject:

I remember my dad having "problems" of some sort with the existing transducer, which is probably why there's a brand new one sitting in a box. The problems could have been due to the location as you say... who knows at this point.

He was well aware of the potential problems of the cored hull, so I'm fairly certain that was handled properly. In fact, he probably bird-dogged that installation so much I should send a sympathy card to whomever did it.

I'm going to go with Garmin electronics... still in the process of narrowing the models and components.

I'll get more details when I get back out to the boat again.