problems with depth finder

[bearriver]

I bought a Bottom Line Tournament 320 last year and put it on my 18 foot ProV. It took me a while to get the right angle on the transducer but finally got it. It ran great for most of the summer but now just reads fish all of the time. When I come down off of step, I have to reset the depth finder just to get a reading of the bottom. I have a minkota 24 volt trolling motor set-up, the depth finder is hooked up to one of the batteries, would there be any feedback off of the 24 volt system? any ideas would be great!

[Rost]

Take the unit off "Demo" mode .

I could be wrong on this, but I have never seen a sonar hooked to the trolling motor batteries. I believe it is best to hook them up to the cranking battery.

Is it a glass or aluminum boat? If it is aluminum, sometimes the rivets create air pockets that make it hard for the unit to read bottom. I'd try lowering it a touch.

[The_Duckslayer]

Mine runs off the trolling motor battery and I have had no issues with it... One thing that I have found with mine is that it does go into the Demo mode now and again when I put it on the boat. I have a model (don't remember the brand right now and it is to far to walk to the garage to look) that has the removeable head. Suspect those connections may need to be cleaned. Might look at that. Have a good one and N Joy the Hunt././Jimbo

[stick]

I had the same exact problem with my bow mount depth finder. It did end up being the fact that I had it connected to one of the trolling motor batteries. I pulled the wires back to my accessory battery, and viola...perfect. I would certainly start there.

Good luck.

[stick]

By the way, BearRiver...are you from Bear River up north (by the Sturgeon Lake chain)? I'm originally from Hibbing...good to meet 'ya.

[andy j]

I have used trolling batteries in the past with no problems. It might just be because it is a Bottomline, They have gone down hill in popularity over the last few years. I had a 2 a few years back and they both were junk. I think they are the Fisherprice of sonars. Anybody else think that hooking up to the trolling motor batteries is a problem. If it is could you hook up somewhere up front like splicing to the nav. light wires?

[Gus]

I would have to say that if you have your batteries wired together so they are 24volt for the trolling motor and you have the depth finder hooked to this battery setup it is most likely your problem. I'd definatley start there. Hooking it up to just one of the batteries may not be just giving it 12V because of the rest of the system. I guess I would definatley start there.

[Chris Haley]

I would run it off your cranking battery also. Guy's that haven't had problems with depth finders running off trolling motor batteries are lucky!!

Does it work fine on plane?? If it cuts out when on plane it could be a transducer problem also.

[Surface Tension]

From your description of the problem I'm sensing your sounder is shutting down when I sees a drop in voltage caused by the trolling motor.

[ChuckN]

Yup, re-wire it to the cranking battery!! Too much interference and power demand from the trolling motor.

[stick]

A quick test is to just run some wires to another battery that is isolated from the trolling motor. I am at least finicky about having neat wire bundles in my gunwales. I did a 15 minute check and was able to do it in the garage. I ran the D-F (a Lowrance X-85) and then started up the motor. I got all sorts of "clutter" on the screen. Then I disconnected the wires, and temporarily wired dragged wires back to the cranking battery. When I ran the electric then, no problem. I was very relieved and haven't had a problem since. I agree that those doing it and not having a problem are lucky. I think any D-F manual will tell you not to connect to the trolling batteries due to electrical "noise" injected into the system. I was surprised since DC systems are normally not prone to noise, and AC circuits are where that comes into play. However, it is a no-no in this case. (talk in electrical engineering from UND...GO SIOUX!!!)

[Fisher Dave]

I have had issues in the past with having the depth finder hooked to the trolling motor battery... It had varied from motor to motor, and graph to graph... yes, sometimes it would be reading fish everywhere when the troller was turned on .. interfearence... when the batteries were getting low, the voltage display would pop up and show me my voltage was getting too low, and the depth finder would turn itself off with some type of safety shut off(not all graphs have this feature).

This can sometimes happen when running off your cranking battery also... fish everywhere.. probably interfearence from the charging system on the main motor.

Some depth finders are very finicky about power fluctuations.. others you could hit with a bolt of lightning and they would still read properly. I have gone as far as running my depth finder off a seperate lawn mower battery to avoid all the interfearence(sp??) from other electronics running in the boat..

You would think someplace would come up with some type of surge filter(for lack of better definition) for individuals having this problem... they came up with something for car sterio's.. wonder if it would work in a depth finder application?

[bearriver]

Thanks guys! I will try to hook up the depth finder to the cranking battery and see what happens. And yes, I am from Bear River way up Nort'! I remember even when I have both the trolling motor and running motor shut off for the big drift, I would still get alot of feedback. Any thoughts on this one?