If it has electric start then yes it does.
I have a 1988 mercury classic 50.
It runs like new. My fish finder is connected to the starter battery.
The voltage never changes. But doesn't drop below 12v. Does this motor charge the battery?
Did it ever?
Sent from my SM-A716U1 using Crappie.com Fishing mobile app
If it has electric start then yes it does.
Test the rectifier.
Yours should look similar to this and its a common failure point.
Rectifier for 1988 Mercury 50 HP 1050312BC, 1050312BD, 1050412BC, 1050412BD Boat | eBay
Chris
Here's a simple explanation of how to test it.
Mercury Outboard L3, L4, & L6 Rectifier Test - YouTube