Depth lost over about 15 knots

[Bigplumbs]

On 2 of my boats where I have Garmin transom mounted transducers and garmin chart plotter combo and Striker 4 depth equipment. I loose the depth information (Depth just flashes and holds the last depth it had). when on the plane and over about 15 knots. Both these boats have outboards and I have mounted the transducers on the starboard (Right) side of the motor on the transom as the garmin instructions.

I was wondering if anyone else gets this and what a solution might be

Thanks


Dennis

[Fenlander]

Drop the transducer a little?

On my Aerotec to get a constant reading I have the transducer on a wooden leg that is a little deeper than ideal from the drag/splash point of view but it rarely if ever loses readings.

[Poly]

It’s very common. If you get any air between transducer and water it will stop working, or if the transducer ends up in turbulent water.

I’ve never worried about it - if I am at planing speed I am confident about the depth below me. They measure the depth where boat has just been, at speed, by the time it calculates, displays, and my brain processes it I will be several boat lengths away from whatever it saw.

[paintman]

Originally Posted by Poly

It’s very common. If you get any air between transducer and water it will stop working, or if the transducer ends up in turbulent water.

I’ve never worried about it - if I am at planing speed I am confident about the depth below me. They measure the depth where boat has just been, at speed, by the time it calculates, displays, and my brain processes it I will be several boat lengths away from whatever it saw.

Ditto.

[jonp]

As pointed out it could be air bubbles travelling under the hull then getting under the transducer. Putting the transducer deeper is often not a good idea as the extra drag depending on your top speed could break the bracket, transducers only need to be just skiming under the surface.

When setting up a transducer have someone drive the boat while you look over the stern for the least airated water passing under the boat, then mark this area with a waterproof marker. Follow the installation instructions, if you have done this and still experiance loss of bottom angle the transducer so that the back part of the transducer is lower than the front by 5mm ish ( sending the pulse forward).

I'm not aware of garmin settings but if there is a setting in the menu to increase the ping speed then put this high ( this is the speed of the pulse sent from the unit ). If the pulse and transducer angle are to slow and angled the wrong way you may simply be passing the returning pulse before it gets back to the transducer.

For me I find it extremely important to have the equipment I've paid good money for to be doing its job to the best it should. I use transome mounted transducers which will easely pick up and hold bottom at all speeds out to 300+ metres, still showing bottom in depths deeper than 500m at slower speeds from a relatively cheap standard transducer.

In water up to 30m my sidescan transducer will also produce good results, for deeper water I have to slow up which isn't surprising as sidescan is doing a heap of work in deep water.

Simply don't accept poor results, a little tweaking should soon have you running at speed with good results.

[Bigplumbs]

So after reading many replies I have lowered the transducer on all three boats by about 8 mm and have rotated it to point forward more by one click. It actually looks much better now. We will see.


Thanks for all the advice


Dennis

[Bobg]

I had a similar problem, the solution was two part.
Angle the sensor such that it was horizontal when on the plane.
Antifoul the bottom of the sensor to stop anything growing on it.
It now works fine.

[Nos4r2]

Oddly, the in-hull transducer in my Searider works at all speeds, but I have the same problem on the Ballistic. It loses the signal for both structurescan and normal depth as soon as it's coming on the plane.

I don't think there's a solution in my case-the scalloped hull shape is even visible in the wake so I'd have to have the transducer so deep it'd keep flipping up. But then as Poly says, I'm only planing where I'm confident of the depth. Having a 250 quid prop does that for you