Transducer placement on 180 Sportsman

Libertas

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Sportsman
Good morning folks,
I have a Garmin GT56TM (and Garmin HD transom bracket with spray shield) I'm about to install with a Stern Saver and my goal is pretty simple I hope, track bottom at speed and achieve optimal performance without causing any issues. Also hoping to do this only once since I have a clean transom with previous holes filled and matched gelcoat restored. So, I'm looking for feedback from anyone who's transom mounted a Garmin or other large 3d side view transducer on a smaller Grady with a single outboard.
Garmin states 15" from propeller and when you add half the propeller width that lands me roughly 22" from centerline and right on top of my starboard bunk just inside the strake which is not ideal. So a couple of questions...
1) Has anyone installed one of these large transducers (small ones are much less a factor) inside the 15" propeller clearance recommendation without causing cavitation on the motor or turbulence on the transducer that shows up as noise, and if so how far in from the centerline was your measurement?
2) Has anyone experienced any turbulence from the bottom strake closest to the keel that only runs the front third of the wetted area, or is it far enough forward it's not a factor?
I've added a few photos to show the strake I'm questioning, 20251018_180900_resized.jpgthe starboard bottom to show its clean with no other obstructions,20251018_180826.jpgand of the transom area where I'll be mounting.20251018_135740_resized.jpg
Thanks in advance for any feedback and I look forward to hearing from you fellow GW owners.
 
I'd put it in this vicinity (see the yellow area).

The bunk has no impact on the transducer usage. If the bunk sticks out past the transom, just cut it or move the boat back slightly on the trailer as long as you have some tongue weight to spare.

Also, don't get too caught up in wanting to hear from someone with a "Grady" - the boat brand has no impact, either.

IMG_5542.jpeg


Good morning folks,
I have a Garmin GT56TM (and Garmin HD transom bracket with spray shield) I'm about to install with a Stern Saver and my goal is pretty simple I hope, track bottom at speed and achieve optimal performance without causing any issues. Also hoping to do this only once since I have a clean transom with previous holes filled and matched gelcoat restored. So, I'm looking for feedback from anyone who's transom mounted a Garmin or other large 3d side view transducer on a smaller Grady with a single outboard.
Garmin states 15" from propeller and when you add half the propeller width that lands me roughly 22" from centerline and right on top of my starboard bunk just inside the strake which is not ideal. So a couple of questions...
1) Has anyone installed one of these large transducers (small ones are much less a factor) inside the 15" propeller clearance recommendation without causing cavitation on the motor or turbulence on the transducer that shows up as noise, and if so how far in from the centerline was your measurement?
2) Has anyone experienced any turbulence from the bottom strake closest to the keel that only runs the front third of the wetted area, or is it far enough forward it's not a factor?
I've added a few photos to show the strake I'm questioning, View attachment 39708the starboard bottom to show its clean with no other obstructions,View attachment 39709and of the transom area where I'll be mounting.View attachment 39707
Thanks in advance for any feedback and I look forward to hearing from you fellow GW owners.
 
Here’s a stern saver with a Garmin side scan/clear vu transducer on a Grady 215.
I also glued (epoxy) one tie wrap block for the transducer cable above the stern saver so I had no drill holes below the water line.IMG_2794.jpeg
 
Here’s a stern saver with a Garmin side scan/clear vu transducer on a Grady 215.
I also glued (epoxy) one tie wrap block for the transducer cable above the stern saver so I had no drill holes below the water line.View attachment 39711
Thank you for the reply! Looks like yours is mounted about a foot away from centerline and I'd love to get mine that close. Any issues with engine cavitation or transducer turbulence (display noise) while under way, and what speed are you still able to track bottom?
 
I'd put it in this vicinity (see the yellow area).

The bunk has no impact on the transducer usage. If the bunk sticks out past the transom, just cut it or move the boat back slightly on the trailer as long as you have some tongue weight to spare.

Also, don't get too caught up in wanting to hear from someone with a "Grady" - the boat brand has no impact, either.

View attachment 39710
Thanks for your response. I'm aware of the bunk not factoring when the boat's in the water. The area you highlighted is where measurements show it should go, but I want to push the envelope and get it closer for several reasons. I'm asking fellow GW owners because the hydrodynamics of the SeaV² hull are unique as is every hull design and also why I asked for feedback specifically from owners of smaller single engine GW boats with these specific types of transducers because the hydrodynamics of those setups determine the answers to my questions.
 
Thanks for your response. I'm aware of the bunk not factoring when the boat's in the water. The area you highlighted is where measurements show it should go, but I want to push the envelope and get it closer for several reasons. I'm asking fellow GW owners because the hydrodynamics of the SeaV² hull are unique as is every hull design and also why I asked for feedback specifically from owners of smaller single engine GW boats with these specific types of transducers because the hydrodynamics of those setups determine the answers to my questions.
The bunk doesn't factor in while it's on the trailer, either (see what I wrote).

Truthfully, there's nothing special about this hull in terms of what we're talking about. I (and guys at my shop) have done so many ducer installs over the decades... it's just a simple install - looking for obstructions that could cause turbulence -- or being too closs to the prop to cause the prop to venitlate (not cavitate) is all you need to look for.

I'm intending this in just a straight up answer (not rude or sarcastic)... it's just a hull. Water flows off the back of that hull like it does any other hull. It's good to think about this... but you're over thinking it. Put the ducer on and go boatin'!

Actually, even the hull saver thing is overthinking it - I have never EVER had an issue over 30+ years drilling into many, many transoms. It's all about doing it right. That's not to say that using the HS is a bad thing - it's fine. I guess more of a personl preference - but my point is that the ads all get people thinking that drilling into a boat is this horrible thing and the boat is going to rot and sink. That's advertising at it's finest :)
 
Thank you for the reply! Looks like yours is mounted about a foot away from centerline and I'd love to get mine that close. Any issues with engine cavitation or transducer turbulence (display noise) while under way, and what speed are you still able to track bottom?
Zero issues. Transducer itself was mounted slightly lower in the rear than the front. That’s an adjustment on the transducer bracket. Boat would touch 50 mph light and never lost depth reading, although I never exceeded 200’ depth. The side scan feature was interesting. I could cruise by a dock and it would show pilings and fish, even displaying distance from transducer to target. Clear Vu (depth) would show a gator laying on the bottom, along with fish, bait and shrimp in numbers.