Help with transducer placement

[MikeR13]

Hey Guys…Currently have transom mount transducers namely ss904, tm54 dff3d and 175 chirp.

Currently have all three mounted in the center between my twin engines. I start to lose bottom around 20 mph and my auto range jumps all over the place because of the loss of bottom. I have a feeling this is happening because my motors are counter rotating and putting the wake so to speak between the motors. I am considering moving a couple of the transducers to the opposite side of each motor to reduce water turbulence and the rotation of the props. Do you think there’s a minimum distance radially that they away from engine? Or give me any ideas to improve at speed as they are all mounted 1/8” below hull

My boat is a 27 ft aluminum hull. Photo for reference

 

[Deep Blue]

MikeR13,

Can you provide pictures of the vessel's transducer installation..?

- Deep Blue

 

[MikeR13]

Attached are pictures for assistance. I can move around pretty easy so any advice would be great

 

[Deep Blue]

MikeR13,

While I'm not a big fan of placing transducers that close together, I don't see anything on where it's mounted that would be causing your turbulence. However, there are no pictures posted on what is in front of that transducer, and that may be the issue.

Here is the recommendation on mounting transom transducers between any outboards/outdrives, and you seemed to have followed the correct mounting location. However, you didn't supply any pictures forward of the transducer that could be the cause of your turbulence issues:


- Deep Blue

 

[MikeR13]

MikeR13,

While I'm not a big fan of placing transducers that close together, I don't see anything on where it's mounted that would be causing your turbulence. However, there are no pictures posted on what is in front of that transducer, and that may be the issue.

Here is the recommendation on mounting transom transducers between any outboards/outdrives, and you seemed to have followed the correct mounting location. However, you didn't supply any pictures forward of the transducer that could be the cause of your turbulence issues:

View attachment 6197
- Deep Blue

Thanks for reply! I don’t have rivits or strakes in front of transducers since it’s welded hull and smooth.

I was thinking too many transducers to close together likely the issue. Thinking of moving the dff3d to center and the others outside of the engines.

 

[Deep Blue]

MikeR13,

That is a good possibility that's the issue due to the transducers being so close together and causing turbulent water to fan out and splash across the all transducer face(s).

Could you temporarily remove two of the transducers, (just unbolt them and then tie them up above the vessel's transom..?) leaving only one transducer in place and retest at speed to see if the turbulent issues then go away..?

- Deep Blue