Hummingbird issue

[bandrus1]

Hi all.

 

I have a hummingbird 859 on my boat and last year, starting at 90 feet the bottom reading started getting messed up. If u see in the photo, the bottom image is about 10-12 feet above the # of feet of depth. The unit is reading perfectly fine up until 90 feet and then it starts messing up. I purchased a new transducer and it kept happening. I put my helix 5 head unit on the same transducer and still happens. My only thought is 2 years ago I had my transom replaced and they moved the mount location and it's now too high?

 

IV tried many different settings and it seems like the vintage is right

 

 

 

[bandrus1]

Here is a picture of the transom mount.. you see to the right is the old location 

[sherman brown]

On 7/5/2025 at 2:50 PM, bandrus1 said:

Here is a picture of the transom mount.. you see to the right is the old location 

 

that could be your problem. the transducer is much too high and should be lowered just a little below the bottom of the boat. i have mine where the bottom of my transducer is below the bottom of my boat with the top part of my ducer above the bottom and tilted slightly up in the front, so I get a smoother water contact on the bottom of my ducer. try this on your ducer and I'm almost positive it will cure your problem.