Been trying to figure this out with no luck so far. Turns out that the sonar (Lowrance StructureScan) works just fine if I turn on the trolling motor OUT of the water ? Today I tried adding a ground wire to the case - didn't think it was possible but it made it worse.
So tho it often gets me into trouble, got me to thinking. Since I can turn on the trolling motor out of the water and get no interference, maybe I should do the opposite of adding a ground to the case ?
When I added the wire, I checked it with my meter and could only find a small spot where I would get continuity. So in my great wisdom, I thought I needed more bare metal, so scratched some paint (powdercoat I think) off of a small area - basically just scratched it with a screwdriver.
Good continuity then, but interference was worse when I dropped the motor in the water.
Sooooooooo, may be a stupid thought, but since it works fine out of the water, could my problem possibly be there should NOT be ground to the case ? Was thinking what if I isolated the case from the water - simply "painting" the case. I wouldn't use actual paint as that would chip off too easy, was thinking something like POR-15 - a coating that dries rock solid, is used to prevent rust as the coating keeps air from getting to the metal.
Unless i could figure out a way to wrap it in a plastic bag....lol...kidding.
Just seems strange I only get the interference when the motor is in the water (is not the wake - happens on the lowest speed and instantaneously - wake from the motor would not have time to go inches from the motor - oh, forgot - transducer is mounted on the transom.....
am I nuts or maybe on to something ?
So tho it often gets me into trouble, got me to thinking. Since I can turn on the trolling motor out of the water and get no interference, maybe I should do the opposite of adding a ground to the case ?
When I added the wire, I checked it with my meter and could only find a small spot where I would get continuity. So in my great wisdom, I thought I needed more bare metal, so scratched some paint (powdercoat I think) off of a small area - basically just scratched it with a screwdriver.
Good continuity then, but interference was worse when I dropped the motor in the water.
Sooooooooo, may be a stupid thought, but since it works fine out of the water, could my problem possibly be there should NOT be ground to the case ? Was thinking what if I isolated the case from the water - simply "painting" the case. I wouldn't use actual paint as that would chip off too easy, was thinking something like POR-15 - a coating that dries rock solid, is used to prevent rust as the coating keeps air from getting to the metal.
Unless i could figure out a way to wrap it in a plastic bag....lol...kidding.
Just seems strange I only get the interference when the motor is in the water (is not the wake - happens on the lowest speed and instantaneously - wake from the motor would not have time to go inches from the motor - oh, forgot - transducer is mounted on the transom.....
am I nuts or maybe on to something ?
.