Stereo noise when motors running

[Jfair]

I installed a Kenwood stereo that works great but as soon as I start the motor the stereo gets real choppy from motornoise feedback. Any suggestions as to what to do?

 

[Jfair]

Re: Stereo noise when motors running

Oh by the way I ran a new ground wire back to the bolts holding the motor on to check the ground and it did the samething....

 

[rallyart]

Re: Stereo noise when motors running

If it's a whine that is related to RPM it might be the Alternator. An isolating capacitor can fix that.
Your description seems like it's for of a loud static. That would likely be a boken plug wire or distributor noise. It should be worse with higher engine load rather than just higher RPM. Replacing the wire set would likely fix it but it could be arcing at a coil or the distributor making the noise. It's basically a radio interference caused by very high voltage and not shielded.

 

[Jfair]

Re: Stereo noise when motors running

The motor is a 125 merc outboard that seems to be running great but I will replace the plug wires to give that a first shot.I should of put that info up with my post....ya think maybe resistor plugs????

 

[salty87]

Re: Stereo noise when motors running

how long is the run and what's the gauge of the wire?...both power and ground?

 

[paultjohnson]

Re: Stereo noise when motors running

The motor is a 125 merc outboard that seems to be running great but I will replace the plug wires to give that a first shot.I should of put that info up with my post....ya think maybe resistor plugs????

Heck ya resistor plugs! I would do that before plug wires

 

[Jfair]

Re: Stereo noise when motors running

how long is the run and what's the gauge of the wire?...both power and ground?

Cant remember what gauge but its tied to the fuse block under the dash so its maybe a foot long run and the wire is a heavier gauge than whats coming out of the back of stereo. The ground is a short run also but I hooked it up to several different spots and get the same results.

 

[canyonken]

Re: Stereo noise when motors running

Try running the power wire directly from the stereo all the way to the boat battery and make a power connection at battery.
I do one better - I use one of those jump box type portable units to power my stereo. My starter battery for boat is not used at all to power stereo. I can sit all day long and run the stereo without drawing anything from boat battery. I take the jump box back home after weekend and plug it in and charge it up gain for next time. Also - I always have the jump box handy if anything did happen to the boat battery on the water. I never have to worry that I am running the stereo too long without having to start boat to make sure it will start later in day.

 

[Jfair]

Re: Stereo noise when motors running

Try running the power wire directly from the stereo all the way to the boat battery and make a power connection at battery.
I do one better - I use one of those jump box type portable units to power my stereo. My starter battery for boat is not used at all to power stereo. I can sit all day long and run the stereo without drawing anything from boat battery. I take the jump box back home after weekend and plug it in and charge it up gain for next time. Also - I always have the jump box handy if anything did happen to the boat battery on the water. I never have to worry that I am running the stereo too long without having to start boat to make sure it will start later in day.

Tried that and samething...could'nt get resistor plugs so I went and bought noise filters at Rafioshack. The car audio places strangely didn't have them . After clipping on the power wires I hit the ignition and the noise is all cleared up...radio sounds great