trouble with fish finder

[conron]

I have a hummingbird 500 series and had it on a jon boat that I sold, then bought a bow rider and installed it on this boat and now i cant seem to get it to work properly. when I moving at any rate of speed the depth reads 1.5 feet. worked fine on the jon boat and the temp reading seems to be fine. any ideas fellas

 

[marcortez]

Re: trouble with fish finder

My guess would be the transducer is not mounted properly.

"at any speed" indicates that the water turbulence at the stern is causing this false reading.

Make sure the transducer is at, or just slightly (1/8th") below the bottom of the boat.

Check to see if the same problem exists when the boat is not moving and no water turbulence is involved.