Tomcat Thru Hull Chirp Ducer- good idea?

Westie

Hi again,
My Airmar TM150M Transom Mount CHIRP Transducer looks to be flaking out. It had been fine since install Dec 2014. When I changed fluids two weeks ago, we cleaned it up real nice and carefully. Ever since, it just cannot hold bottom. I don't think it changed angle but that is something I'll check when I get a chance to pull it out again.
If that isn't the cause, I was considering using a thru hull transducer. I did some searching but I didn't see anything related to a 2006 Tomcat. I didn't look super hard as this is a secondary option....however, I thought I'd toss out the topic nonetheless. The primary use is fishing, so I need a strong signal.

thataway · Posted: Sat Sep 17, 2016 10:58 pm Post subject:

The problem is where are you able to put the transducer? The entire bottom of the Tom Cat is in contact with trailer bunks when you winch it onto the trailer. I suppose if you never trailer, it would be OK.

It is a long way down to work--to properly put in a thru hull transducer, you will have to remove core, fill this area with thickened epoxy, so that there is an area to compress when you tighten the thru hull transducer nut uno tight on the inside.

If you are thinking of using a "Shoot thru the hull" that is a different issue, and core has to be removed, then solid glass filled this area, finally a box, dome etc, has to be made for the transducer and fluid to sit in, or you can epoxy (way down the line, use silicone) the transducer in place. I don't have any experience with the CHIRP and shooting thru the hull--should work--not sure which transducer you would use.

I would bet on the angle, or something on the transducer, if it only happened after a clean up...

Westie · Posted: Sat Sep 17, 2016 11:02 pm Post subject:

Thanks Bob - I should have said, "shoot thru hull".

gulfcoast john · Posted: Sun Sep 18, 2016 6:59 pm Post subject:

Westie,
Maybe just bad luck, but I consider getting 2 years out of any transom mount ducer par for the course. When something hits it at 30-40MPH those delicate ceramic parts inside it fall apart. Saltwater marine life clings to 'em.
When out of the water, put your ear up to it and listen for a ping. If none or it's irregular, it's dead. Don't turn it on out of water for long. Don't paint it with a copper base bottompaint.
I use a N2K network depth only to the N2K backbone at the transom (since most leads are too short to and too much trouble to fish through all the way to the 741 or 4212 MFDs at the helm). It just quit pinging at 18 months. I tried putting the spare in a zip lock bag of (fresh) water in the sponson behind the bilge pump, held in place by a couple of baggies of sand, and that works pretty good for my purposes (despite core) while protecting the ducer from the ravages of salt water and hitting debris. I might keep it there.
However, I can't imagine how a CHIRP SideVu could work shooting through the hull. You could always try this baggie trick, but my bet is you need a new ducer, since it's been almost 2 years.
Have Fun!
John

Westie · Posted: Sun Sep 18, 2016 7:57 pm Post subject:

Thanks John. I'm planning to buy another and do a temp install to see if its the ducer.

thataway · Posted: Mon Sep 19, 2016 12:07 am Post subject:

There will be some attenuation with a standard transducer shooting thru the hull. I have used this in most of my racing sailboats. Most could hold the bottom at 600 feet, which was plenty for me.

Just the issue of the core, and how to bed it..As to the Chrip--should be OK--I would contact the manufacture, or AirMar who makes most transducers (except some Garmin, which are made in house). Use a baggie full of water to see if you can find a place in the aft hull of the Tom cat which will work--Not sure if the "sump" there has no core or not...

Any core, and no workie.