Help with transom mount transducer placement

[EagleOCNJ]

I finally got my boat in the water with a new look after a year long makeover.

I dropped it in started 'em up no problem and idled a few minutes then worked my way up to about 35 knots.

I looked back and saw water blasting off of my motor and up in the air. I shot a rooster tail of like 20 feet! Damn it - it was my transducer. I determined that it is mounted a bit too low 1/2 inch below the boat) and may be in a bad spot? I mounted it low in hope that Id get a reading from it a speeds.

The first ducer is at the bottom point of the V with the garboard plug - this one works good. The second ducer is on the port side. Where should it be in relation to the chines/strakes or whatever they are called.

I am bummed out that I have to yank the boat again and fix the ducer at the ramp tommorrow. I need help before I waste my time and get it wrong again.

[JW-Tex]

I have always heard to mount on the starboard side-the water is suppose to be cleaner (assuming the motor is not a counter rotator).


No advice on how far to have it below the hull, mine is mounted inside the hull in a pvc pipe with cap submerged in mineral oil.

[Fr. Frank]

Mount in so that the bottom of the 'ducer is 1/8" below the hull, with a slight angle forward. I recommend just inside of the inner hard chine, so that at higher speeds it will still get a reading.

Note, however, that at speeds above 35 mph, even the bottom hard chine can catch air. When my Humminbird Matrix does that, I don't get a good reading again until I slow down below about 22-23 mph.

A shoot-thru hull transducer avoids that issue, but then you gotta put in faring blocks to get it vertical and all kinds of other stuff.

[warthog5]

Mount in so that the bottom of the 'ducer is 1/8" below the hull, with a slight angle forward.

Yep. A 1/8in below at the transom and a 1/4in below at the aft end of the ducer. [Slight tilt looking forward]

I should also be on the STB side. Every instruction sheet that comes with a ducer tells you that.

[EagleOCNJ]

I did it no problem and no more rooster. Thanks- now my lights and some elects dont work. Geez!

[PipeDreamsMarine]

John.. I had the same problem with mine even after I did the same things. I really bugged me to have the water blowing of the motor. So I made up a little spray shield that I mounted right next to the trans.. stopped the problem and didn't effect the transducer.

[EagleOCNJ]

Don,
It ended up being no big deal; yes a PITA but a couple hrs at Tenn Ave and back in. No more rooster.