Install alternator? - 1984 Johnson V4 90 hp

[tahall3]

I own a Cobia Sunskiff 156 with a 1984 Johnson Seahorse V4 90 hp outboard on it. I usually use a starting battery and a deep cycle for all of my accessories (radio, fishfinder/gps, nav lights, spotlight, etc.) and naturally, the deep cycle drains pretty quick and takes a long time to fully recharge. May be a dumb/naive question, but is there any way to install an alternator/generator on the engine, even if it would only slow down the rate of discharge on the deep cycle? Any responses greatly appreciated.

-Tim

 

[Daviet]

Re: Install alternator? - 1984 Johnson V4 90 hp

The engine should already have a charging system on it, maybe it is not working.
Put a volt meter on the battery terminals with the engine not running, should show about 12 volts. Start the engine and run it about 1500 rpm and see if the voltage goes up, if it does your charging system is working.

 

[emdsapmgr]

Re: Install alternator? - 1984 Johnson V4 90 hp

On most boats, the engine and accessories are connected to the starting battery. If you have a second battery for additional accessories, usually it is charged via an on-board charger. That charger can be plugged in when the boat is back at the dock or at home on the trailer. It is possible to install an A/B Battery switch so that the engine charging can be directed from one battery to the other. Keep in mind that your engine charger only puts out around 10 amps, not a lot of charge unless you travel long distances with the boat. Most marine shops/dealers sell the A/B switch.