Depthfinder Problems?

[gitnby]

I have an Eagle 480 Fishmark mounted on my trolling motor, which has been a good unit for me until lately.

Sometimes it's right on, works fine and then it will jump around to 227' or 431' or some strange depth?

At first I though I was getting interference from my other unit, but even when I power the other one off it does it.

Doesn't seem to be any rhyme or reason as to when it happens.

I have checked everything I know to check?

Any ideas? Sound like a bad transducer or cable? Or should I take the unit in for repair?

[Sam]

I run an Eagle on my trolling motor and a Humminbird with the transducer at the back of the boat on my dash. They both do that and always have, a couple of times every trip. I just turn off the power, turn it back on, and they read right again.

It happens to my depthfinders when they get "confused". The main one shows all kinds of crazy depths (400+ feet) when I run the boat at top speed, and once in awhile it doesn't go back to normal when I slow down. The one on the trolling motor sometimes gets mixed up when I pull the motor up to move, and then put it back in the water. Sometimes the transducer on that one gets bumped too, and if it isn't at a 90 degree angle to the trolling motor shaft that'll throw the readings off.

If the false readings only happen a couple of times per fishing trip like with my depthfinders, and if it reads right again after being turned off and back on, I'd consider that normal. If it happens often enough to be a problem, then something's not right.

When my depthfinders get confused like that it's after the receiving of a return echo was interrupted, one because the boat was moving too fast and the other because the transducer was out of the water. That might be a clue if you have to track your problem down.

[Paul Nienhaus]

Look at the tansducer surface, if it is scuffed up try polishing the transducer face with very fine sandpaper.

[Dutch]

Check your manual for reset procedures, it may be a software problem.

[CaptainJoe]

[b]I have an Eagle 480 Fishmark mounted on my trolling motor, which has been a good unit for me until lately.

Any ideas? Sound like a bad transducer or cable? Or should I take the unit in for repair?

You might want to try mounting on the bow. They do not work underwater.

I am sorry.....I just could not pass that one up. Thanks for the laugh.....

[Gary Lange]

Call the Marine Repair Center, 514 N. Prince Ln., Springfield, Mo. 65802 at 417-833-9191 and talk to them and discribe your problem. I am sure they can advise you what needs to be done.

[flipper]

my 480 did that, had a bad place on the cable . I spliced it and taped it real good. been working fine since.I priced a new transducer and they aint cheap 80 bucks shipped . 50 bucks 2 years ago.

[Frost1920]

I have the same model (Eagle 480) and have had it for 4 months or so. It does the same thing every once in a while. It usually doesn't happen when Im just fishing. It goes crazy after I pull the trolling motor up and then put it back in the water at the next spot. It only happens once in a while, and not every trip. I haven't really though about it being a problem until I read your post. Hopefully it doesnt get worse. Id be interested to hear the outcome of your story if you end up taking it in for repair.

[Sam]

Yeah, mine's an Eagle 480 too, and as I said it does the same thing occasionally.

The other strange thing it does sometimes is to exactly double the depth - if I'm in 28 feet of water it'll read 56 feet, etc. The sound waves must do a double bounce somehow, who knows? Anytime it gets stupid, the cure is to turn it off and back on again and then it's OK.

[gitnby]

Thanks for all of the suggestions!

I think the transducer just needed a good polishing?

Worked great this weekend! Not one problem!