Motor Not Charging Battery While Running

[CM45]

I have a 2003 50 hp four stroke on my boat. Yesterday I quickly found that the motor was not charging the battery while it was running. The motor ran the battery down in a relatively short time. I could see the voltage going down on the voltmeter. The motor alarmed out and shut off when the battery got too low. I was able to switch the leads to the trolling motor batteries, I have two in parallel, and was able to get back to the marina. I could see that those batteries were draining while running as well.
My question, is where is the alternator located on the motor. Is is part of the starter. I would like to replace this myself if it is not to difficult to get to.

[gatorglenn]

Your motor has a voltage regulator, and a stader. Regulator is on the starboard side of motor. Box about 3” square. And the cheapest think to replace. The stader is under the flywheel, and is a little more involved to replace. The system needs to be tested, starting at the battery and back. But if your not hearing all kinds of weird noises, and squealing. It’s probably not the stader. And the regulator is not letting power get to the battery.

[CM45]

Gatorglenn,
Thank you for your input. This gives me a good place to start looking. There are no ill sounds coming from the engine so the regulator sounds like the it could be the issue. I will start working from there.

[BDPIL]

I have an 05 60hp and noticed my motor not charging my cranking battery as well. Ended up being the regulator. Easy and cheap repair.