EASY, EASY Grashopper these men are telling you what is true, and of their experience and personal knowlage is a gift to you. Never, Never tell someone not to impart there knowlage to you, take it in and put it to use. These men are giving advice to us to steer us in the direction so we can fix our problems. And if you feel that someone makes you feel like a idiot that is a personal condition that you need to deal with. But if someone wants to make you feel incompetent then it should be your goal to show them otherwise. Now if someone just out-right called you a idiot or stupid then I believe you have the right to rant about it. Personally i'm at the stage of life I like people to think I'm a idiot and go through great lenghts to propitiate that interpretation of myself. It keeps the needy folks at bay.
OK now to your post, we all know what is needed for a NORMAL system to work. And I for one believe you have the mechanical ability to figure it out. However I don't think we are all coming over to your place this weekend to BBQ drink beer and work on your motor, go back through all your test, Check the system with a different meter (is the battery good in yours you can get some funny stuff with a week battery) Forget about the amps and the voltage on the fish finder. Trace all the wires out completely, do not take anything for granted if you do it will bite you on the rear. Do you have a service manual if so make use of it to help with your quest. I know you'll figure it out and let us know what is going on with your motor, which will en-lighten all of us.
However it your charging can not be explained and you say your motor is running fine you may just have to let this one go. Although I for one don't believe in the devils triangle, Big foot or space aliens. But Santa Clause and the tooth fairy I have proof! Once you figure it out it would behoove you to make nice, nice with racerone as he is just trying to help you.
Racerone, patience, patience. Now Joe don't blame Al Gore he invented this thing the internet don't your remember. However I do think Al Gore is a Idiot, now that,s not a political opinion, or a personal attack on the man it's just my personal opinion of the man.
So anyhow i would like to personaly thank all who post tech advise on this site directly to my threads and to the others as I read as many as possible and try to glean some sort of knowlage from them to use with my problems!