Transducer question

[MR fisher]

Toward the end of last summer I picked up my first saltwater fishing boat (21’ Fiberform). I spent a few weeks then working on mechanical things and fished it a few times. Overall things are going well. I’ve got it winterized now and my plans over the next while are to rewire it (typical old rat’s nest wiring job) and work through a list of little issues.

One of the relatively small issues is the sonar/GPS. The boat came with an old Garmin fishfinder and a Lowrance Elite-7 HDI. The previous owner only used the Lowrance for the GPS and the Garmin for sonar. He told me that the Lowrance didn’t work as a sonar. After a bit of investigating and messing with settings I found that the sonar did in fact work but that I couldn’t get great output on the display (best I could get was on 83 kHz frequency, as seen in photo). I traced the cable down to the hull and found a transducer mounted in epoxy there (Photo 2). Although I’m new to the saltwater game, it didn’t look right to me as a through hull transducer. I found the label on the transducer and it appears that it should be transom mounted. I’m not sure what led to it being placed where it is, but that’s where it is.

What I’m looking for is some suggestions for where to go from here. My plans are to fish local Vancouver waters most of the season, with hopefully a couple of WCVI trips over the summer. I want good, reliable sonar output in those waters, but don’t need/can’t afford the best of the best.

 

[MikePA]

Toward the end of last summer I picked up my first saltwater fishing boat (21’ Fiberform). I spent a few weeks then working on mechanical things and fished it a few times. Overall things are going well. I’ve got it winterized now and my plans over the next while are to rewire it (typical old rat’s nest wiring job) and work through a list of little issues.

One of the relatively small issues is the sonar/GPS. The boat came with an old Garmin fishfinder and a Lowrance Elite-7 HDI. The previous owner only used the Lowrance for the GPS and the Garmin for sonar. He told me that the Lowrance didn’t work as a sonar. After a bit of investigating and messing with settings I found that the sonar did in fact work but that I couldn’t get great output on the display (best I could get was on 83 kHz frequency, as seen in photo). I traced the cable down to the hull and found a transducer mounted in epoxy there (Photo 2). Although I’m new to the saltwater game, it didn’t look right to me as a through hull transducer. I found the label on the transducer and it appears that it should be transom mounted. I’m not sure what led to it being placed where it is, but that’s where it is.

What I’m looking for is some suggestions for where to go from here. My plans are to fish local Vancouver waters most of the season, with hopefully a couple of WCVI trips over the summer. I want good, reliable sonar output in those waters, but don’t need/can’t afford the best of the best.

Could be a bubble in the epoxy making the reading not so clear. If you want a dedicated shoot through hull transducer.. the airmar p79 works just fine. If you want a transom mount the P66 works great for the price.

 

[wildthing]

Can only second what MikePA says if the hull is foam inlaid then a shoot through wont work so your better off with the p66 transom mount it's the same 50/200 element but you'll get a speed wheel as well ... don't think the elite was ever updated to chirp so going with a tm165 hw is prob a waste or any other chirp transducer ....

 

[Sr SQ]

As the others have recommended a transom mounted transducer will give you the best results.
You could try prying off the Lowrance one, it may not be that well adhered but even if it comes off undamaged and you come up with the brackets it won't be as effective as a P66

 

[easydoesit]

All good advice above.

With the equipment you have you could set up one system as your main fishing sonar and have the second as a backup. This is what I run having had a couple of transom mount transducers knocked off by wooden stuff while running. One time was the first day of a 6 day trip.

Main System - your Lowrance with the P66

Backup- Your Garmin with a shoot through transducer, often works better than transom mount at planing speed and adequate for trolling. epoxied inside the hull.

 

[MR fisher]

Thanks guys. I don't think the hull is foam inlayed, but I will confirm. If I can I think I would go with a shoot thru hull to replace rather than transom mount. Just keeps it out of the way. All things being equal I would expect better sonar returns that way too, wouldn't I?

 

[wildthing]

grey area but shoot thur's tend to lose Q power so it all boils down to the thickness of the boat hull in a few rare cases it can equal a transom mount but would not worry to much as long as it will pick up bait and show depth when trolling thats most important its not going to give you a great pic when your running 20+ mph knt's