Does my 15 hp johnson charge the battery?

Well unfortunately the 9.8 Mercury I had is bad to much to fix I found a 1989 15 hp Johnson motor very clean with electric start I hope this is a good motor did some research I don’t believe I have a rectifier which I believe means no charging system. I was told I can use a small lawn mower battery is that enough for 1 day of fishing then recharge when I get home? I’m guessing 5-6 times of restarting or do I need a regular battery hoping to keep the weight down in the boat. It does have pull start and starts at half pull so far.

If it’s electric start from the factory,it should be capable of charging the battery and will have a rectifier.As far as a battery,that would be ok unless you are running other items off of it.

Put a volt meter on it and see what the voltage is before you start it and if it increases, 12.5-13 volts before to 13.5-14.5,while it is running, it is more than likely charging the battery.

IMO the 1980s OMCs represent the absolute peak of small 2 stroke outboard design. They are better than Mercury IMO just because they are so much simpler and more elegant in their design. The 15 Electric Start is a gem and the best sub-25 HP 2 stroke ever.

I have rescued several of these 15 HP electric start OMCs from barns and boathouses. With a little TLC they roar back to life and just keep going. EW

Does it charge? Yes! It has a stator with rectifier. OMC never made an electric start small outboard without a charging system, they all use the very basic stator system that is very reliable and mercifully rather cheap to replace if it does go bad. Unlike–cough–I’m looking at you, Mercury.

Test voltage at the battery, but you must have a good meter. Don’t expect 14.5 volts and 50 amps just sitting there idling, this is not an alternator! At fast idle you’ll probably get about y13 volts, so curb your enthusiasm. These are made to keep a battery charged, not bring a zombie battery back from the dead. At WOT you might get 13.5 to 14 volts. Obviously this test must be done with lower unit in water or running on muffs.

My advice is to jump on that outboard like an alligator on a poodle if it’s in good condition and running. Even if the stator is not currently working (unlikely), it’s worth having it fixed just to own a gem like this. 50 to 1 mix of Penzoil Premium Plus 2 stroke oil and she’ll run forever.

Grouse

Thanks guys getting it today! I will only run the motor on it and charge every few days

Hope you get it.

I can tell you that when I sold the ones I’ve owned, my phone was on FIRE for the electric start models. On freaking fire. Unlimited demand for the e-start models, they were that good.

Grouse

My 78’ish isnt electric start but I sure understand the popularity of this motor. I almost feel bad for wanting to replace it. At least it should be easy to sell when the time comes.

Motor runs awesome wow it runs good a lot different than my 30 hp 4 stroke Yamaha but a close second.

EVen if it does charge a little, put a trickle charger on. It will not replace what electric start uses in a reasonable amount of time. Also, if you start the motor without a battery hooked up, you can wreck the system. If it has one.