Assistance with transducer location

[Augoose]

All,
Would I be OK mounting the transducer as show in the attached photo- just to the right of the drain? Its a small humminbird transducer and according to their instructions they state that as long as it is 15" away from the prop it should be ok. However, in their manual illustration they show it 15" to the side, not in front of the prop like in my plan. From the prop, it seems my potential mounting location would be well over 15".

The reason I want to run it there is so that I can run the cable for the transducer along side of the pitot tube without having to drill new holes - and so that I can use the same transom hole as well.

I've read that mounting a transducer in front of the prop can cause cavitation but I'm hoping that mine is so small and it would sit enough to the side that I wouldn't run into that issue.

The surface of the hull in front of that mounting location is smooth so I wouldn't expect any turbulence however would it be too close to the pitot?

Thoughts?
Thanks!

 

[Pez Vela]

Re: Assistance with transducer location

There is really no way to be certain which mounting location will result in the best performance of the transducer until you try them, and your hull/transom configuration provides quite a challenge. The 15" recommendation is to the starboard side of the boat's centerline, when (as in your case) you have a single prop. There are a variety of ways to temporarily attach the transducer. I would test several locations without drilling any holes or putting any screws into the transom until you're satisfied with the results. Even when you've found the best spot, I would permanently mount the transducer using something akin to the HomePage | THE STERN SAVER system.

 

[Augoose]

Re: Assistance with transducer location

Thanks Pez Vela- I actually made a mounting base out of two pieces of ploy cutting board. I glued the two pieces of 1/2" board together (so that it's thick enough to screw in the transducer mount) with Loctite marine epoxy and then the 3/4" SS screws which mount the transducer mount to the cutting board are long enough to further suck the two pieces of poly together as well. I then plan on gluing the cutting board mount to the transom with the marine epoxy. I really didn't want to drill holes in my transom!

I was then going to use some 3M dual lock velcro (link) to temporarily hold the transducer in place for a trial run.

 

[Silvertip]

Re: Assistance with transducer location

What do you suppose is going to happen if that assembly comes loose?? Hitting the prop and cutting the cable are pretty good guesses. Where do you plan to run the transducer cable.

 

[Augoose]

Re: Assistance with transducer location

What do you suppose is going to happen if that assembly comes loose?? Hitting the prop and cutting the cable are pretty good guesses. Where do you plan to run the transducer cable.

I'll probably lose the transducer and won't find any fish!

I suppose my gel coat could crack and fail allowing it to come off but based on some tests I did I really don't think that's going to happen. I found that a 3"x3" poly surface area covered in marine epoxy had much more bonding strength than two screws did when I tried to pry it apart with a screw driver. Based on that adhesion, the poly should mate up equally as well to the transom and provide a better bond that two screws could. Also, for my application my boat is on a trailer when not in use so water intrusion over time of the marine epoxy will not be an issue for me.

I came up with the materials based on several articles I read on the matter with many of the applications being used for several years without issue. Not to say that my plan won't fail, but I just don't want to drill into my transom.

Lastly, I'll be running the cable along side of the pitot tube and if I tether the cable up and inside the transom, even if the transducer breaks free there will not be enough slack for it to reach the prop - nor could it swing up and smack anyone seated in the rear of the boat. The prop is well below and behind the mounting location of the transducer anyway....

I appreciate the comments

 

[UncleWillie]

Re: Assistance with transducer location

That location will be fine for down looking sonar.
It will be an issue if you have Side Scan.

 

[Augoose]

Re: Assistance with transducer location

That location will be fine for down looking sonar.
It will be an issue if you have Side Scan.

It is indeed downward looking- thank you!

 

[Augoose]

Re: Assistance with transducer location

Got the system installed - works great and the marine epoxy seems to be holding very well. Ran at 45 mph for about 40 mins with no issue whatsoever. Even though we were marking plenty of fish, we couldn't catch any of them! :facepalm:

 

[Pez Vela]

Re: Assistance with transducer location

EXCELLENT! Thanks for the update. You probably will have to slow down to catch any fish.

 

[Augoose]

Re: Assistance with transducer location

LOL - THAT was the problem!!!!:facepalm: