Tolling motor interference with fish finder

[bryan121]

Was out on the water yesterday, and my fish finder would work fine with the big motor running, or when drifing, but once I ran the trolling motor the graph was all distorted and interfered with. This has never happened to me before, and the only thing I noticed was that the trolling motor also had a small chime in it as well. Minnkota trolling motor with co-pilot and an eagle fish finder. Any suggestions?

[whitebassman]

Had that problem last year. Only interfered when the trolling motor was running. turns out the connection was loose, and not screwed in completely, causing unshielded interference. Running an Minnkota terrova ipilot.

[SpecialK]

Is your fish finder on the same battery(ies) that power your trolling motor? If so check your connections as was stated earlier but think about a dedicated battery for your main motor and electronics.

[Dusty]

I had bought a new Minnkota with a built in transducer. I had a lot of interference from the motor to my sonar. I found out I had to ground the trolling motor batteries to the boat, It cleared it right up.

[eurolarva]

I had bought a new Minnkota with a built in transducer. I had a lot of interference from the motor to my sonar. I found out I had to ground the trolling motor batteries to the boat, It cleared it right up.

I am pretty sure you do not want to ground your electronics to your boat (aluminum boat) Outboards have a sacrificial anode that is designed to protect the motor from galvanic corrosion. Over a period of time I am pretty sure you will be turning your whole boat into a sacrificial anode which will start to corrode your boat. The best solution is to run the graph on the starting battery which should not be grounded to the trolling batteries.

[Bigtom]

I had the same problem on my bird and minkota Terrova, so I ran power to my starting batt. Also I swiched to advanced mode on my depth finder and it popped up new menus and options to change sensetivity.