Depth Finders Gone Wild

[janalon]

I have a Lowrance XP-25 that has all of a sudden started giving a false bottom as soon as I start getting on plane. I am thinking that I may need to reset it to factory settings or something.

The Transducer is on board.

If I slow down and almost stop, it starts reading the bottom again.

Does anyone have any idea what may be causing it.

[preach4bass]

I've read that this is a result of air bubbles interfering with the transducer.  The best place to find out (beside here) is Lowrance's web site.  Go under their tutorials and they answer about every question imaginable.

[Cujo]

i had problems similar with mine.  it was the one on my trolling motor.  i must have bumped it off a stump or rock (the transducer) and it had turned a bit on its side and everytime i would use speed 4 or 5 it would goof up.

[Yankee_Bassman]

My Humminbird mounted at the driver's console has a transducer epoxied in the bilge. It won't give a reading at speeds over 20 MPH or so.  It's mounted in a bad spot, just as preach4bass said. Bubbles or an airpocket form above that speed, and send the transducer haywire. It's not a big deal for me, as I don't fish much unfamiliar water, and rely on my bow finder when I'm actually fishing.

If yours suddenly started acting up but worked before, I'd check the transducer first, to be sure it hasn't come loose, or doesn't have a bad connection that vibrations at higher speed create. Then I'd check the hull, and lower unit, to be sure there isn't a gouge or ding that's causing the hull to generate turbulence that didn't occur before. Even slight damage can change the dynamics enough to affect the transducer, but not enough for you to notice in handling.

[janalon]

Thanks for all your input and advice.

I think that my prop needs replaceing. I really think that this is where all the interference is coming from.