Yes, any metal to metal contact that vibrates does create electromagnetic impulses that can create interferance, makes no difference what type motor, even an electic motor could cause it. Chances are good that it was the throttle connection at the throttle arm on the motor. Glad you have the problem corrected, regardless of cause. As a general rule, never used metal clevisis on a metal arm. If two metals must touch, make sure the connection is very firm, absolutely no play.