Starter/generator

[catfish918]

Let me ask if you have a ground from your engine to the frame and a ground to the battery? The potential can be different as the engine in many cases are setting on rubber mounts. This is true of any electrical device when dealing with a non conductive material fiberglass, plastic, rubber, etc... You mentioned you thought you had a weird ground issue, well you may have. The solution is to run grounds to the frame and to the battery, it insures the potential to be the same.

[catfish918]

In some vehicles they have a positive ground, so to make a radio work that it designed for a negative ground you have to float that ground. I don't mean to complicate the issue but all your equipment is secured to fiberglass then in short the ground is being floated. Some trucks and older cars and tractors were designed that way. I have run wires from the case of the radio to the metal frame of the speakers to get around the issue.

[catfish918]

I will try to help you, I was a radio technician in the Marine Corps, and then I spent better than 20 years doing Instrumentation and Automation at a Chemical facility. However not being there it's difficult for me to understand all the symptoms. So you have to bear with me, when I ask if have done some of these things.

[catfish918]

Were there any differences between the head units, the speakers, the antenna, anything you had to modify to put the new unit in?

[catfish918]

Some electronics are designed to operate in a very narrow voltage range, usually computers being one of the more sensitive devices. Your new head unit may have limitations and you'll need to contact the manufacturer to find that out. They simply shut off so to speak when outside the range in order to protect itself. In some older vehicles when you went to start the vehicle the radios would shut off due to the voltage drop. The light would stay on but sound would go silent.

[swhite832]

As to the ground issue.

The ground goes from the engine to the starter to the frame to the battery. All cleaned and dialectic grease added

Stereo install - no modifications

When I hooked up to an external battery, the only thing that was actually attached to the cart was the antenna....same issue whenever accelerator depressed. When I disconnected the antenna the problem went away except for a momentary speaker shut down.
The antenna is connected to the fiberglass shell only. Its weird. I have installed a lot of stereos in a lot of things and have never had such a weird issue.
BTW Im USMC too 88-92

[catfish918]

Semper Fi! You are right that is the weirdest scenarios I've ever heard of. On the bottom side of your antenna can you clip an external wire onto the threads of the antenna and connect it to the negative of the battery? Very strange.

[swhite832]

Originally Posted by catfish918

Semper Fi! You are right that is the weirdest scenarios I've ever heard of. On the bottom side of your antenna can you clip an external wire onto the threads of the antenna and connect it to the negative of the battery? Very strange.

Great idea!!
Ill try it.

[catfish918]

Or you can just hold the antenna next to something you know is grounded, like you do to check the spark on a sparkplug. Then try it again.

[catfish918]

I have never encountered anything even remotely like this before.