My buddy has a 1991 Champion with a 150 Mercury Mariner.(dont know if thats relevent but thought I'd put it in there) He has a 82 lb thrust Motor Guide trolling motor. He would like to know where is the best place to mount the transducer on his trolling motor? Directly under shaft?

Hopefully he has the TM mount style transducer. Those attach to the bottom of the TM prop head unit.

I thought maybe I should elaborate. He has been having trouble with interference. He thinks maybe he has the transducer in the wrong place. Its @ the very bottom of motor, directly under the shaft. Should it be as close to the front as possible? I cant imagine it should go close to the prop as this would probably make things worse. Any other feedback as to why he doesnt get a clear reading would help. Cart, thanks for the response. Dont mean to sound stupid but what is a tm mount style transducer??

He has been having trouble with interference.

Does he leave the console FF on while the TM one's on?

console ff is turned off............and he still has trouble.........

console ff is turned off............and he still has trouble.........

Ok - Is it wired to the TM battery or the cranking battery?

It is wired to the crankin battery............

It is wired to the crankin battery............

Is there anything else on that circuit which could be causing the interference? For example, does he have a marine radio on it? He should try to eliminate all the possible sources of interference in the power circuit or on the boat itself. Once he's done that I couldn't tell him where to go next - maybe a good shop could help or maybe somebody else here may have another idea.

Thanks man! I appreciate the input!