10-06-2012 03:56 - edited 10-06-2012 03:58
I have a ticking noise on FM and AM radio. I have a 2012 250 HO. It's ok on MP3 input.
I tried an antenna filter, grounding the antenna, grounding the chassis, running ground directly to battery and it doesn't change. Didn't have it on my 1995 225. Next step will be running stereo off of a stand alone battery to see if it's the radio picking up the interference.
If you can hear a ticking noise that is gone when the motor is turned off, it may be a plugwire or sparkplug that is leaking voltage or arcing. If this is the case, you will hear the ticking change freqency as the throttle is opened up.
Often this situation is found when a new motor is installed on an older boat and there is some type of interaction or interference in the wiring.
Sometimes as simple as moving the antenna can make a difference.
"There is never just one thing wrong with a boat";
-- Travis McGee, main character in a book series by John D. McDonald
The factory recommends that a properly trained technician service your Johnson or Evinrude outboard motor. Should you elect to perform repairs yourself, use caution, common sense, and observe safety procedures in the vicinity of flammable liquids, around moving parts, near high-temperature components, and working with electrical or ignition systems.
The information offered here is only general in nature and should not be construed as complete factory approved procedures, techniques, or specifications. Always use the proper service manual for your motor, up-to-date service literature, the correct tools, and have an understanding of how to proceed with troubleshooting and repair methods. If you are unsure or uncomfortable with a procedure, a situation, or a technique, enlist the services of a factory trained technician.