Kevin,

Here is a boat wiring diagram for the marine electrical on my 2008 Clearwater 2200WA with a 225HP Yamaha.

I have a two battery configuration where one is used for starting and the other is the house battery for electronics and the like. I have both boat batteries connected via a dual circuit marine battery switch (5511e) and both batteries are charged via isolated leads from the outboard since this outboard provides an accessory charging lead in addition to the primary lead to the starting circuit.

I keep both batteries off via the battery switch when the boat is not in use and the only direct wiring to the battery is for the bilge pump float switch.

The other day, I could not start the motor because of a discharged starting battery after the boat had sat for several days. I switched to the combine mode and the motor started. Ran all day with no issues.

Two questions, please: Is there a problem with the boat battery wiring or charging circuit? Will this circuit accommodate a battery charger if the boat battery switch is in the off position?

Thanks.

Frank

Hi Frank,

This is a great marine electrical system and the dual circuit PLUS battery switch is one of the key components. My best guess on the dead battery would be the device that is connected to the mystery red lead connected to your starting battery (at the switch). It is probably a stereo memory wire or some type of memory device.

With the switch in the off position, you will need to use a dual output battery charger or manually connect your charger to one battery and then to the other. If you are installing a dual output charger, I strongly recommend connecting the battery at the switch and your ground bus and not at the battery. Too many battery connections become confusing and the mix of small and large wires on the terminals always causes a loose connection.

Hope this helps and nice wiring diagram,

Kevin

Kevin,

I am currently restoring and repowering a 20′ Bertram.

The boat is a stern drive with both batteries in the motor box. I have already purchased an automatic smart battery switch and an eight switch marine electrical panel.

This boat helm is very far forward. The boat will be used exclusively in salt water and I want to have a very “heavy duty” boat wiring job. All the equipment will be run to the forward helm and some accesories like

1. Bilge pump
2. Diaphragm pump
3. Washdown pump
4. Bilge blower
5. Navigation  lights

…will be needed to run back to the motor box. All other accessories will be mounted near the forward. helm.

Here are the other accessories on the marine electrical system:

• Stereo
• Boat horn
• Engine room lights (also run to the stern)
• Gunnel lights
• GPS
• VHF

I need a harness to accomodate all of this.

Your thoughts?

Thanks.

Marshall

Hi Marshall,

To do this job correctly, I would recommend that you build a completely custom boat wiring harness. The best place to start is with our wiring size calculator. Use this to determine what size wire your components require along with the size of the panel board feed wire.

Tinned wire in standard boat wiring colors and most sizes is available on our sister marine wiring site.

Good luck with the project. Please send pictures of the electrical portion of this restoration and we will post them on our site.

Thanks

Kevin

Hi Kevin,

I have a 2005 19’6” SeaPro Fish and Ski boat.

I did not use the boat for a year while we moved from Florida to Washington State.

Last week, I decided to get the boat ready to go in the water, I checked my battery, which checked OK. Assuming everything was OK, I took the boat to the water. The motor started up like a champ. The hydraulics work, but I have no power to the marine electrical switch panel or any of the switches that turn on navigation lights, radio or my depth finder.

I checked the 3A feed wire fuse and it looks OK. I cannot get 12 volt in the 12 V outlet for auxiliaries.

What could be wrong?  I checked the circuit breakers, but can’t tell if they are OK or not.

Thanks,

Jesse

Hi Jesse,

The 3A fuse is probably for a bilge pump auto switch or some other low draw device in your marine electrical system.

The main accessory power feed should have at least a 20 amp fuse.

If all accessories are inoperative, the problem is either the power feed or the ground for your fuse box.

I would check the boat battery cable connections and follow them up to the boat’s fuse panel.

You will find the problem,

Kevin