Fish Finder doesn't read bottom accurately anymore - Help?

[PCPete]

I have a hummingbird 386CI that has served me flawlessly over the past 300 hours of service. Last week I went out and it started showing bottom inaccurately. Instead of where it actually is it shows 20 feet or so above where it actually was (according to line counter reel and watching jig drop on screen). I plugged another older (black and white) hummingbird fish finder into the same transducer and it has the same problem. I assume the problem is the transducer but I am looking for some other opinions before buying a new transducer or a new fish finder. The transducer is screwed to the back of the boat just below the bottom of the boat (used a plum line to hang it originally). I inspected it after pulling the boat out but it has no visible damage or wear and tear. 

 

Has anyone else had this problem? Has a new transducer solved it? 

 

Happy to answer any questions - 

 

Thanks,

 

-Pete 

[Sk8man]

It sounds like the transducer for sure if it did the same thing with both units. When they become damaged  there usually is no visible sign of it.They can be damaged by something hitting them coming on the trailer wrong and hitting metal, hitting solid objects in the water, or perhaps a stone hitting them while trailering down the road etc.. My hunch is a new transducer will solve it.

Edited June 20, 2016 by Sk8man

[Knotlost]

Yup transducer. But befor you buy one contact them. They had s bad batch and replace them for free.