Yamaha Battery Isolator System

[louiefl]

I have a 2003 150TXRB 2-stroke carb engine that I am looking to relocate the two batteries to the console from the bilge and reusing my Perko 1/2/all/off switch. It is my understanding that this engine has a built in lead for charging a house battery separately. I was told to connect the starting battery to switch terminal 1, house battery to switch terminal 2, and a lead from the rectifier / regulator to switch terminal 2. Accessories would also connect to terminal 2. The theory is that you run the engine with switch on battery 1, and the engine charges battery 1 through the main cable and the house battery through the rectifier lead. Is this correct?

What lead is it on the rectifier / regulator? There is a black lead with a ring lug, a red lead with a spade, red lead with a circular connector, and multiple wires on a circular connector. Do I need a second battery switch between the regulator and Perko switch? Do I need to fuse this leg; if so, what size?

 

[Silvertip]

I generally dispute having all accessories stuck on the house battery for the simple reason that you therefore reduce the capability of the switch. My thought is to put everything, including the engine on the COM terminal. You now have the best use of available power. You can start the engine on either or both batteries, you can charge either or both batteries, and you can run everything in the boat on either or both batteries. You become an electric traffic cop and direct the current to come FROM the desired battery or batteries, or charging current to go TO the desired battery or batteries. Use the switch to your advantage. Everyone seems to be so afraid of a dead starting battery so they install a dual battery switch and then use only part of it's capability. The only thing you might want to wire directly to one battery or the other would be an automatic bilge pump. With this configuration you also don't need to worry about the isolator feature.