Ok, so i have a 100hp 1969 merc1000, and it wont plane, i dont know what to do, i think there might be a loos throttle cable but i dont know where to look to fix it.
If you think you have a loose throttle cable, then the issue is at one end of it or the other. Take the cover off and look. We can't see your engine so you need to give us a little more to go on. Did this suddenly happen or did it come on gradually. Did you just acquire this boat or what?